Hi guys, i need your help.

1)

a- Write a function in java or python that takes 2 inputs: - A plain text that only contains letter characters from the English language. Can be a size of string from 0 to 10. - A key that is a number from 1 to 26 (a mod operation should be used in the key: if 27 is given, the key is 1). - Cipher text that is created by shifting the plain text to right in English Alphabet according to key.

b- Write a function in java or python that takes 2 inputs: - A cipher text produced from section a. - Same key from section a. Gives 1 output: Plain text that is created by shifting the cipher text to left in English Alphabet according to key.

2)

You are given a software that takes the Social Security Number (SSN) of an individual and checks it in its database to verify it.

Please discuss, with examples, what can constitute threats against each of the given requirements (1 example for each is enough): Confidentiality Integrity Authenticity Accountability Availability