Bob created a risky business venture plan and decided to regularly send electronic versions of it to Alice (who is out of town on business) for review, but he knows that his notorious (evil?) business...

Bob created a risky business venture plan and decided to regularly send electronic versions of it to Alice (who is out of town on business) for review, but he knows that his notorious (evil?) business competitor Malice maintains an office near enough to attempt to monitor his communications in the computer network

(a) Bob first needs to establish a new key with Alice for communication (even though Malice is monitoring), without meeting physically with her. Explain how he could use cryptography to achieve this

(b) With your help, Bob solved the previous problem. Next, Bob is concerned about sending so many copies of the plan, providing so much ciphertext for attackers to study to attack his key with, so he’d like to create a separate key and share it with Alice for message encryption. Propose a cryptographic technique to protect his new, 2nd key and explain how to use it here

(c) Bob also wants to ensure that Alice knows each message containing the plan is from him (not someone else), since Bob has old business competitors that may attempt to interfere with their messages. Propose a
a cryptographic technique to prove the messages are from Bob and explain how to use it here