REFACE Consider the following definitions within the context of an asymmetric cryptosystem
Alice is the owner of a pair of asymmetric cryptographic keys
PUBA - her public key
RIV A - her private key
Bob is the owner of a pair of asymmetric cryptographic keys
PUB8 - his public key
PRIV8 - his private key

Encrypting a message can be represented withe the following:

A-> B: M
Alice sends Bob a message M C is a ciphertext

M is a message
K is a key
E( ) is an encryption algorithm D( ) is a decryption algorithm H( ) is a hashing algorithm
C=E(m1,k1)
You get the ciphertext by encrypting the message with Key K1
M=D(c1,k2)
You get the message by decrypting the message with Key K2 h = H(M)

You get the hash of message M
Use the above definitions to show how to provide security to communications between Alice and Bob. Below is an example:
Alice encrypts a message with her public key and sends it to Bob:
A-> B: E(M, PUBA)

QUESTIONS :

1. Show how Alice can send a message to Bob that preservers ONLY the confidentiality of the message.
2. Show how Bob can send a message to Alice that enables Alice to verify the integrity of the message.
3. Show how Alice can send a message to Bob that preserves the message's confidentiality while also providing Bob the ability to verify the message's integrity.
4. Show how Bob can send a signed message to Alice that includes his digital signature.

Acetylene is a gas which burns rapidly on its own, and is considered highly explosive. a) true b) false

This question involves a class named textfile that represents a text file. public class textfile { private string filename; private string filename; private arraylist words; // constructors not shown // postcondition: returns the number of bytes in this file public int filesize() { } // precondition: 0 < = index < words.size() // postcondition: removes numwords words from the words arraylist beginning at // index. public void deletewords(int index, int numwords) { } // precondition: 0 < = index < = words.size() // postcondition: adds elements from newwords array to words arraylist beginning // at index. pub lic voidaddwords(int index, string[] newwords) { } // other methods not shown } complete the filesize() method. the filesize() is computed in bytes. in a text file, each character in each word counts as one byte. in addition, there is a space in between each word in the words arraylist, and each of those spaces also counts as one byte. for example, suppose the words arraylist stores the following words: { mary had a little lamb; its fleece was white as snow. } the filesize() method would compute 4 + 3 + 1 + 6 + 5 + 4 + 6 + 3 + 5 + 2 + 5 as the sum of the lengths of each string in the arraylist. the value returned would be this sum plus 10, because there would also be 10 spaces in between the 11 words. complete the filesize() method below: // postcondition: returns the number of bytes in this file public int filesize() { }

Identify the publisher in this citation: carter,alan.a guide to entrepreneurship.new york: river’2008.print.