Answer:
computer is an electronic machine that accept raw data ,process and then give result. it's uses:
It is used for storing data and information.
Answer:
D. Spreadsheets
Explanation:
While A also seems correct, a spreadsheet is best at collecting and organizing data. Databases would only store data while a spreadsheet would keep those records, as well as help calculate a budget or payroll.
Answer:
In assembly language, two instructions control the use of the assembly language procedure.
CALL pushed the control to the return address onto the stack and transferred the control.
RET instruction returns the address that placed on the stack by a call instruction.
Explanation:
Action RET instruction
- The RET instruction pops the address and returns off the stack, which is pointed by the stack pointer.
- The stack is LIFO in memory at a particular location, and the pointer points offset from the stack location.
RET instruction does its job by consulting the register and memory state at the point when it is executed.
In RET instruction, only register and memory state is executed. Call instruction must save that address that figure out in a register and memory location.
D. They provide a platform for collaboration
Answer:
The fundamental limitation of symmetric (secret key) encryption is ... how do two parties (we may as well assume they are Alice and Bob) agree on a key? In order for Alice and Bob to communicate securely they need to agree on a secret key. In order to agree on a secret key, they need to be able to communicate securely. In terms of the pillars of IA, To provide CONFIDENTIALITY, a secret key must first be shared. But to initially share the key, you must already have CONFIDENTIALITY. It's a whole chicken-and-egg problem.
This problem is especially common in the digital age. We constantly end up at websites with whom we decide we want to communicate securely (like online stores) but with whom we there is not really an option to communicate "offline" to agree on some kind of secret key. In fact, it's usually all done automatically browser-to-server, and for the browser and server there's not even a concept of "offline" — they only exist online. We need to be able to establish secure communications over an insecure channel. Symmetric (secret key) encryption can't do this for us.
Asymmetric (Public-key) Encryption
Yet one more reason I'm barred from speaking at crypto conferences.
xkcd.com/177/In asymmetric (public key) cryptography, both communicating parties (i.e. both Alice and Bob) have two keys of their own — just to be clear, that's four keys total. Each party has their own public key, which they share with the world, and their own private key which they ... well, which they keep private, of course but, more than that, which they keep as a closely guarded secret. The magic of public key cryptography is that a message encrypted with the public key can only be decrypted with the private key. Alice will encrypt her message with Bob's public key, and even though Eve knows she used Bob's public key, and even though Eve knows Bob's public key herself, she is unable to decrypt the message. Only Bob, using his secret key, can decrypt the message ... assuming he's kept it secret, of course.
Explanation:
