In the ARM Cortex CPU programmer's model, the high registers are R8 - R15.
Group of answer choices
a. True
b. False
Answers
The high registers in the ARM Cortex CPU programmer's model are not R8 - R15 is false statement. Therefore option b is correct.
In the ARM Cortex CPU programmer's model, the high registers are not R8 - R15. The ARM Cortex CPUs have a 16-register banked architecture, where registers R0 - R7 are considered the low registers, and registers R8 - R15 are considered the high registers.
The low registers (R0 - R7) are general-purpose registers that are always accessible in all execution modes. They are used for general data operations and temporary storage.
The high registers (R8 - R15) are also general-purpose registers, but their accessibility depends on the execution mode. In some execution modes, the high registers may be banked, meaning that multiple copies of these registers exist for different purposes or privilege levels.
For example, in the ARM Cortex-M series processors, which use the Thumb instruction set, the high registers R8 - R15 are divided into two banks: the user bank (R8 - R12) and the exception bank (R13 - R15). The exception bank is used for storing the stack pointer and link register when entering an exception or interrupt handler.
Therefore, the statement that the high registers in the ARM Cortex CPU programmer's model are R8 - R15 is false.
The low registers are R0 - R7, while the high registers encompass a different range depending on the specific architecture and execution mode. It is important to understand the register layout and access rules of the specific ARM Cortex CPU being used for effective programming and optimization.
To know more about ARM Cortex, visit
https://brainly.com/question/31499671
#SPJ11
Related Questions
Can anybody answer this please
Answers
Answer: Managing memory allocation for all applications (first one).
when determining outsourcing fees, a has a variable fee based on the number of users or workstations that have access to the application.
Answers
When determining outsourcing fees, a subscription model has a variable fee based on the number of users or workstations that have access to the application.
What Is a Subscription Business Model?Subscription business models are known to be those which are said to be based on the notion of selling a product or service to be able to get monthly or yearly subscription revenue.
Note that this model is one that is known to be focus on customer retention over the issue of customer acquisition.
Therefore, When determining outsourcing fees, a subscription model has a variable fee based on the number of users or workstations that have access to the application.
Learn more about subscription model from
https://brainly.com/question/14317614
#SPJ1
When determining outsourcing fees, a ____ has a variable fee based on the number of users or workstations that have access to the application.
Discuss, in your own words, the topic of cybersecurity management for both individuals and business. Briefly talk about the different threats, and then explain what cybersecurity management is, and what it could do against each common type of threat.
Answers
Cybersecurity management protects individuals and businesses from threats.
How does cybersecurity management safeguard individuals and businesses?Cybersecurity management is essential for both individuals and businesses to protect themselves from the ever-increasing threats in the digital landscape. In today's interconnected world, individuals face various cybersecurity risks, such as malware, phishing attacks, identity theft, and data breaches.
Similarly, businesses are vulnerable to targeted attacks, ransomware, insider threats, and intellectual property theft.
Cybersecurity management involves implementing proactive measures to prevent and mitigate these threats. It includes the use of robust security tools, regular software updates, strong passwords, and user awareness training.
Additionally, businesses should employ network monitoring, intrusion detection systems, and incident response plans to detect and respond to any security breaches promptly.
How cybersecurity management works by adopting a layered defense approach, combining technology, policies, and employee awareness. A comprehensive strategy should include firewalls, antivirus software, encryption, multi-factor authentication, and regular data backups.
It is crucial to continually assess and update security measures to stay ahead of evolving threats and ensure a secure digital environment.
Learn more about Cybersecurity
brainly.com/question/30902483
#SPJ11
a system always needs the 4-pin auxiliary power connector, and sometimes needs the p1 connector as well.
Answers
The given statement that a system always needs the 4-pin auxiliary power connector, and sometimes needs the p1 connector as well is false.
At the station's main bus or designated sub-bus, auxiliary power is electrical energy that is supplied by a different source and acts as a backup for the main power source. In contrast to an online unit, an offline unit offers electrical isolation between the main power supply and the vital technical load.
The static inverter in the auxiliary power supply converts the electricity used for interior lighting, displays, air conditioning, etc. The static inverter is installed to provide power that has low voltage and consistent frequency even when there is a propulsive inverter.
Auxiliary power units, sometimes known as APUs, enable aircraft to function independently of ground support machinery such ground power units, external air conditioning units, or high pressure air systems.
Learn more about auxiliary:
https://brainly.com/question/26960026
#SPJ4
What should you look for if you want to know if your web browser session is secure?
Answers
To determine if your web browser session is secure, you should look for a few indicators.
The times to be look forHTTPS - Check if the website URL begins with "https -//" instead of "http -//". The "s" indicates a secure connection.
Padlock Icon - Look for a padlock symbol in the address bar. It signifies that the connection is encrypted.
Security Warnings - Ensure there are no warning messages or alerts indicating potential security risks.
Extended Validation Certificate - Some secure websites display an extended validation certificate, which provides additional verification of the website's authenticity.
Browser Security Settings - Make sure your browser settings prioritize security and warn about insecure connections or websites.
Learn more about secure browsing:
https://brainly.com/question/13354554
#SPJ4
URGENT!!!! What is the concept of using the internet to trade goods and services called?
Answers
Answer:
barter
Explanation:
is the direct trade of goods, services and resources without the use of money
Answer:
e-commerce
Explanation:
just took the test, see pic below
A shop will give discount of 10% if the
cost of purchased quantity is more than 100
Ask user for quantity
Suppose, one unit will cost 100
Judge and print total cost for user
Answers
Answer:
10%÷100 it is correct answer
This function checks if a character is a vowel. If it is, it returns true. Otherwise, it returns false. Where should return false; be written in the code? function checkVowel(character){ var vowels = ["a", "e", "i", "o", "u"]; for(var i=0; i
Answers
Answer:
at the end, i.e., after the for loop.
Explanation:
see code.
I also added a cooler alternative implementation.
The main function's return of 0 indicates a successful program execution. Return 1 in the main function denotes an error and indicates that the program did not run correctly. Returning zero indicates that a user-defined function has returned false. Returning 1 indicates that a user-defined function has returned true.
What return false be written in the code?One of the two values is what t may return. If the parameter or value supplied is True, it returns True. If the supplied parameter or value is False, it returns False.
Because it is a string, “0” is equivalent to false in JavaScript. However, when it is tested for equality, JavaScript's automatic type conversion changes “0” to its numeric value, which is 0; as we know, 0 denotes a false value. As a result, “0” is false.
Therefore, at the end, i.e., after the for loop. I also included a more attractive alternate implementation.
Learn more about code here:
https://brainly.com/question/20345390
#SPJ5
"Caller ID" is the feature that displays the telephone number of the caller on the telephone of the person he or she calls. With Caller ID now routine and widely used, it might be surprising that when the service was first available, it was very controversial because of privacy implications. (a) What aspect of privacy (in the sense of Section 2.1.1) does Caller ID protect for the recipient of the call? What aspect of privacy does Caller ID violate for the caller? (b) What are some good reasons why a nonbusiness, noncriminal caller might not want his or her number displayed?
Answers
Answer: Provided in the explanation section
Explanation:
please follow this explanation for proper guiding.
(a)
i. What aspect of privacy does Caller ID protect for the recipient of the call?
* The beneficiary of the call utilizing the Caller ID highlight becomes more acquainted with who precisely the guest is, independent of the guest being a decent/terrible individual or authentic/ill-conceived call.
* Depending on how the call went or wound up, i.e., the discussion, business, messages passed on, the beneficiary would have the option to act in like manner and suitably dependent on the guest and his message's respectability, habits, morals, demonstrable skill, or telephone decorums, and so forth.
* Also, the beneficiary gets the alternative to choose how to manage the call even before him/her picking the call, when he/she comes to know who the guest is through Caller ID include, the beneficiary gets security by either separating the call, sending or diverting the call, recording the call, not noting the call, or in any event, blocking or announcing the number in any case. Along these lines, the beneficiary's security is ensured from various perspectives.
ii. What aspect of privacy does Caller ID violate for the caller?
* Even however as it were, in fact it distinguishes, confirms, and validates the guest demonstrating he/she is who he/she professes to be. In any case, the guest ID highlight or innovation unveils numerous information and data about the guest, for example, his accurate phone number or PDA number, nation code, the specific phone or versatile transporter organize he/she is utilizing, and so on., as this data may make dangers the guest's security, (for example, character burglaries or just assailants caricaturing others utilizing this current guest's data), classification, it might cause accessibility issue for the guest as when the guest is besieged with ill-conceived calls, spam, and undesirable calls, there are chances their telephone numbers could and would be imparted to many advertising and selling organizations or industry without the guest's assent, there are chances somebody focusing on the guest may tap or wire his/her significant, basic business, social, expert, individual, or private calls for touchy data to assault them and abuse the bantered data. The guest certainly loses his/her secrecy, opportunity, directly for discourse, security, and wellbeing when passing on messages over the call when they know there could be somebody tapping or recording the call, or even the beneficiary may abuse the guest's character and his/her passed on data.
* Hence, the guest doesn't get the opportunity from reconnaissance i.e., from being followed, followed, watched, and spying upon by trouble makers.
* The guest would lose the control of their data on how it would be put away or utilized.
* The guest probably won't get opportunity from interruptions.
(b). What are some good reasons why a non-business, non-criminal caller might not want his or her number displayed?
* A non-business and a noncriminal guest would need to enjoy typical, common, and regular exercises; mingle and do his/her own day by day close to home, private, and public activities' assignments, occupations, occasions, social occasions, correspondences, individuals organizing, and so on., without making any whine about things, exposure stunts, without causing anyone to notice tail, screen, follow, question, or explore the guest superfluously except if the guest has enjoyed, asked, stated, discussed, or passed on any message that is unlawful, exploitative, wrongdoing, and culpable.
* Such a guest would need total or most extreme namelessness, as to them, guest ID innovation just uncovers their own and private life exercises, correspondences, and so forth., to others to pass judgment on them, question them, and later cross examine and research them on their interchanges.
* Such guests for the most part search for security in general.
* Specifically, such guests need classification of their calls, discussions, messages, call logs, and so forth.
* The beneficiary on occasion may get the guest's private unlisted number without the guest's assent or authorization.
* The beneficiary may utilize the guest's telephone number and name to get a lot other data about him/her, which the beneficiary should, that would incorporate the guest's location (area) through an opposite catalog or just turning upward in any phone registry.
* The beneficiary might not have any desire to talk, mingle, or work with the guest in view of the area (address), ethnicity (from the name), race, or district the guest is from.
what is the purpose of a fourier transform in ofdm? group of answer choices transforms time function to frequency function and vice-versa split data streams create frequency overlap digitally modulate the data none of the above
Answers
The purpose of the Fourier Transform in OFDM is to transform time function to frequency function and vice-versa.
The Fourier Transform can be described as an important image processing tool that is used to decompose an image into its sine and cosine components. The output of the transformation represents the image in the Fourier or frequency domain, while the input image is the spatial domain equivalent. The Fourier transform means a representation of an image as a sum of complex exponentials of varying magnitudes, frequencies, and phases. The Fourier transform plays a critical role in a broad range of image processing applications, contain enhancement, analysis, restoration, and compression.
To know more about OFDM Please click on the given link
https://brainly.com/question/29580929
#SPJ4
help i don't know the answer
Answers
A test bed is an environment with all the necessary hardware and software to test a software system or component.
What is meant by hardware and software?The term "hardware" describes the actual, outward-facing parts of the system, such as the display, CPU, keyboard, and mouse. Contrarily, software refers to a set of instructions that allow the hardware to carry out a certain set of activities.RAM, ROM, Printer, Monitor, Mouse, Hard Drive, and other items are some examples of hardware. Software examples include, MySQL, Microsoft Word, Excel, PowerPoint, Notepad, Photoshop, and more.System software, utility software, and application software are some of the numerous kinds of software that can be used with computers.Office suites, graphics software, databases, database management software, web browsers, word processors, software development tools, image editors, and communication platforms are some examples of contemporary applications. software for a system.To learn more about hardware and software, refer to:
https://brainly.com/question/23004660
assume you want to create a class friend and you want to specify that a friend is a human (you want to specify that there is an inheritance relationship between class friend and class human) which keyword should you use in the class declaration to specify that there is an inheritance relationship between the two classes?
Answers
There are various inheritance patterns, including hierarchical inheritance, multiple inheritance, multilevel inheritance, and single inheritance.
What is inheritance?Genetic information is transmitted from parent to kid through inheritance. Members of the same family typically share traits in common because of this.
Examine 5 Different Types of Inheritance Using Examples in C++
Individual Inheritance.Several inheritances.inheritance on multiple levels.inheritance in a hierarchy.Inheritance hybrid.As it relates to genetics, the term "inherited" describes a feature or variation that is encoded in DNA and passed from parent to child during reproduction. The laws of Mendelian genetics govern inheritance.
The final keyword in a class' declaration can be used to prevent subclassing of that class. Similarly, by designating a method as a final method, you can stop subclasses from overriding it.
To learn more about inheritance refer to:
https://brainly.com/question/15078897
#SPJ4
30 POINTS!!
Type the correct answer in the box. Spell all words correctly.
What is the difference between Photoshop and Photoshop Lightroom?
The difference between Photoshop and Photoshop Lightroom is that the latter offers more _____ photo-editing features.
Answers
Answer:
technical
Explanation:
Answer:
i think it is tecnical
Explanation:
Find the TWO integers whos product is 8 and whose sum is 6
Answers
Answer:
2 and 4
Explanation:
The two numbers that have a product of 8 and a sum of 6 are 2 and 4 as an example 2 • 4 = 8 2 + 4 = 6
Answer
What two numbers have a product of 8 and a sum of 6?" we first state what we know. We are looking for x and y and we know that x • y = 8 and x + y = 6.
Before we keep going, it is important to know that x • y is the same as y • x and x + y is the same as y + x. The two variables are interchangeable. Which means that when we create one equation to solve the problem, we will have two answers.
To solve the problem, we take x + y = 6 and solve it for y to get y = 6 - x. Then, we replace y in x • y = 8 with 6 - x to get this:
x • (6 - x) = 8
Like we said above, the x and y are interchangeable, therefore the x in the equation above could also be y. The bottom line is that when we solved the equation we got two answers which are the two numbers that have a product of 8 and a sum of 6. The numbers are:
2
4
That's it! The two numbers that have a product of 8 and a sum of 6 are 2 and 4 as proven below:
2 • 4 = 8
2 + 4 = 6
Note: Answers are rounded up to the nearest 6 decimals if necessary so the answers may not be exact.
Explanation:
HELP ASAP PLEASE!!!
Answers
Answer:
Click and drag the mouse to select the cells
Explanation:
c) From this group, you can crop images in PowerPoint. (i) Adjust (ii) Arrange (iii) Edit (iv) Size
Answers
Under the picture format tab
Question 8 of 10
Which group may provide the best perspective on student life at a particular
school?
A. College deans
B. College professors
C. Freshman-year college students
D. Upperclassmen at the college
SUBMIT
Answers
Answer:
The answer would be D.
Explanation:
Answer:
D. Upperclassmen at the college
Explanation:
when a system is partitioned into pieces, each piece is referred to as a _________________.
Answers
When a system is partitioned into pieces, each piece is referred to as a "partition."
A partition is essentially a section of the system that is isolated and treated as a separate unit. This can be useful for a variety of reasons, such as improving security, enhancing performance, or simplifying management.
For example, a computer hard drive can be partitioned into separate sections for different operating systems, applications, or data.
Each partition can be formatted differently, have different access permissions, or be backed up separately. In summary, partitioning a system allows for greater flexibility and control over how resources are used and managed.
Learn more about partition at
https://brainly.com/question/30191477
#SPJ11
Project manager Kevin has to create a project team organizational chart. Which activity should he perform before creating this chart?
Answers
Answer: C
Explanation: Allocating roles to project team members.
Data mybytes byte 10h,20h,30h,40h mywords word 8ah,3bh,72h,44h,66h mydoubles dword 1,2,3,4,5 mypointer dword mydoubles
Answers
mov esi,OFFSET mybytes will be the first step in the computer system coding within the bytes.
A byte is an eight-binary-character long unit that stores information in the majority of computer systems. Most computers encode an item, such as an initial, numbers, or typographic sign, using a unit called a byte.
mov esi,OFFSET mybytes
mov al,[esi];a.AL=10h
mov al,[esi+3];b.AL=40h
mov esi,OFFSET nyWords+2
mov ax,[esi];c.AX=3Bh
mov edi,8
mov edx,[myDoubles+edi];d.EDX=3
mov edx,myDoubles[edi];e.EDX=3
mov ebx,myPointer
mov eax,[ebx+4];f.EAX=2
A series of bits that must be used in a bigger unit for application-specific reasons can be stored in each byte.
Learn more about bytes, here:
https://brainly.com/question/31318972
#SPJ4
What kind of money is a gold certificate considered to be?
commodity
fiat
representative
currency
Answers
The kind of money a gold certificate is considered to be is: C. representative.
What is a gold certificate?A gold certificate can be defined as a certificate of ownership that is issued by a public treasury and held by the owner of a gold instead of holding the real gold itself.
In the United States of America, a gold certificate is typically issued exclusively to the Federal Reserve System (Fed) by the US Treasury.
In conclusion, the kind of money that a gold certificate is considered to be is representative.
Read more on money here: https://brainly.com/question/25959268
#SPJ5
The kind of money a gold certificate is considered to be is representative. Thus, option C is correct.
What is a gold certificate?A gold certificate can be defined as a certificate of ownership that is issued by a public treasury and held by the owner of a gold instead of holding the real gold itself. In the United States of America, a gold certificate is typically issued exclusively to the Federal Reserve System (Fed) by the US Treasury.
Money is a good that is widely recognized as a means of economic exchange. It serves as the means for expressing values and prices. It is the primary indicator of wealth because it moves from person to person and nation to country, facilitating trade.
Therefore, the kind of money that a gold certificate is considered to be is representative.
To learn more on money, click here:
brainly.com/question/28784237
#SPJ5
12) Which station is the bottleneck? (Hint: some of the steps process both laptops and desktops so it may not be correct to identify the bottleneck simply by comparing the processing rates.)
a. Assembly
b. Burn
c. Packing
d. No bottlenecks
Answers
Because the desktop assembly stage's UPH is 800 units per hour, it will be the bottleneck stage. It is minimal compared to the burning and packing stages.
Both packing and burning follow the same uph for laptop construction. Thus, the laptop is at a bottleneck.
A bottleneck is a congested area in a production system (such an assembly line or computer network) that causes the system to halt or move very slowly. The bottleneck's inefficiencies frequently result in delays and increased production costs.
The word "bottleneck" alludes to a bottle's usual form and the fact that its neck is its narrowest point, making it the most probable location for congestion to develop.
Long-term and short-term bottlenecks are the two basic categories. A transitory bottleneck is one that is usually brought on by transient circumstances.
Learn more about Packing here:
https://brainly.com/question/895838
#SPJ4
dave has been assigned the task of deleting a custom object. after committing the destructive changes, he notices that no feature branch has been created. what could be the reason?
Answers
There was no flag in the Re-Create Feature Branch option.
What may cause a commit to show a status of "No changes"?Base brach was set to master branch and then component was not in production.After setting the base branch to the master branch, the component was not being produced.There was no flag in the Re-Create Feature Branch option.The new version will be added to an existing feature branch if the metadata obtained is different from what was previously obtained.Git does not generate a commit ID if there are no changes, and Copado will display the status No changes.After deploying the destructive modifications, the component must be manually uninstalled in the destination org.Before making any harmful modifications, Ana deleted a component from the source org and updated the metadata index. She can no longer locate the removed component.To learn more about deleting a custom object refer to:
https://brainly.com/question/29215750
#SPJ4
a system uses simple/pure paging and tlb each memory access requires 100ns tlb access requires 5ns tlb hit rate is 90%. work out the actual speedup because of the tlb? speedup
Answers
Each process in the operating system will have its own page table, which will contain Page Table Entry (Memory Management Technique: Paging) (PTE).
What is Translation Lookaside Buffer (TLB) in Paging?The frame number (the address in main memory to which we want to refer) and a few other essential bits (such as the valid/invalid bit, dirty bit, protection bit, etc.) will be included in this PTE. This page table entry (PTE) will indicate where the actual page is located in main memory.The issue now is where to put the page table such that overall access time (or reference time) will be less.Fast main memory content access using a CPU-generated address (i.e., a logical or virtual address) presented a challenge at first. Since registers are high-speed memory, some people at first considered utilizing them to store page tables since access times would be shorter.The concept employed here is to store the page table entries in registers, so that when a request is created from the CPU (virtual address), it will be matched to the correct page number of the page table, which will then reveal where in the main memory the corresponding page is located.Everything appears to be in order, but the issue is that the register size is small (in practice, it can only hold a maximum of 0.5k to 1k page table entries) and the process size may be large, so the required page table will also likely be large (let's say this page table contains 1M entries). As a result, the registers might not be able to hold all of the PTEs of the page table. Therefore, this strategy is not workable.The Complete Question is Page Table Entry.
To Learn more About Page Table Entry refer to:
https://brainly.com/question/15409133
#SPJ4
A user pays for retail purchase by placing a smart phone next to the merchant's reader.Which of the following mobile connections is used?A. MicroUSBB. BluetoothC. LightningD. NFC
Answers
OLAP (online analytical processing) software is the software to perform various high-speed analytics of large amounts of data from a data center, data mart, or other integrated, centralized data store.
What is the use of Online Analytical Processing (OLAP)?OLAP provides pre-calculated data for various data mining tools, business modeling tools, performance analysis tools, and reporting tools.
OLAP can help with Planning and Budgeting andFinancial Modeling. Online Analytical Processing (OLAP) is included in many Business Intelligence (BI) software applications. It is used for a range of analytical calculations and other activities.
Therefore, OLAP (online analytical processing) software is the software to perform various high-speed analytics of large amounts of data from a data center, data mart, or other integrated, centralized data store.
Learn more about Online Analytical Processing (OLAP):
brainly.com/question/13286981
#SPJ1
Elements such as page parts and calendars are easily inserted by navigating to the _____ grouping. Building Blocks Illustrations Text Page Design
Answers
Answer:
Building Blocks
Explanation:
When referring to the Publisher Application the navigation feature that allows you to do this is the Building Blocks feature. Like mentioned in the question this feature allows you to choose from and insert a predefined set of calendars for insertion into a publication as well as insert a variety of other page parts to better customize the feel of the publication.
Hi! Just want to know a cool name suggestion for a game I'm making, I have two options and which one do you think is better?
"CatLit" or "Jumpy Kitty" as the name of a game (quick desc: its an endless game where a cat jumps without stop and aims to move from one block to another while the background scrolls as you go further up, if the cat falls of the screen and has 0 out of 5 lives = gameover)
Answers
Answer:
I like Jumpy Kitty. I think its cute!
Explanation:
Cool that your making a game! Hope it comes out great!
Answer:
I think kitty jump would sound better
Explanation:
because it is an endless game where a cat jumps without stopping
Why do companies collect information about consumers? A. Because they want to meet new friends on social networks B. Because they take consumers' best interests to heart C. Because they want to effectively advertise to consumers D. Because they are looking for good employees to hire
Answers
Answer:
C. Because they want to effectively advertise to consumers.
Explanation:
Companies collect info for more accurate advertisements, which are designed to make people interact with them more commonly.
The web can be modeled as a directed graph where each web page is represented by a vertex and where an edge starts at the web page a and ends at the web page b if there is a link on a pointing to b. This model is called the web graph. The out-degree of a vertex is the number of links on the web page. True False
Answers
The given statement is true.The web graph is a model for a directed graph that helps to represent the web. This model is important because the internet is a vast and complex network of web pages that are linked together. Each web page is represented by a vertex in the graph, and an edge that starts at vertex a and ends at vertex b is created if there is a link on a that points to b.
In other words, each vertex is a webpage, and each directed edge represents a hyperlink from one webpage to another. The out-degree of a vertex is the number of links that point away from it. This means that the number of edges that originate from a vertex is equal to its out-degree. Therefore, the main answer is True. :We can define web graph as follows: The web graph is a model for a directed graph that helps to represent the web. This model is important because the internet is a vast and complex network of web pages that are linked together.
Each web page is represented by a vertex in the graph, and an edge that starts at vertex a and ends at vertex b is created if there is a link on a that points to b.In other words, each vertex is a webpage, and each directed edge represents a hyperlink from one webpage to another. The out-degree of a vertex is the number of links that point away from it. This means that the number of edges that originate from a vertex is equal to its out-degree. Therefore, the main answer is True.
To know more about web visit:
https://brainly.com/question/12913877
#SPJ11
Please help quick i only have 45 minutes left on this test
Answer choices :
radio link protocol
Bob's fingers
laptop
phone company
radio waves
fire trucks
electric current
dispatcher
sound waves
Answers
Answer: phone company, radio link protocol, electric current, sound waves
Explanation: if something is wrong, I'm very sorry