Reference for 1:

Solve only 2:

Suppose that A is a member of an RSA public-key system and that his choices for r and s are r = 53 middot 71 = 3763 and s = 11. If B wants to send the message NOW to A, what is actually transmitted to A? Suggestion Think of the message as NOWX so that two four-digit blocks can be sent Also, use the Russian peasant method to compute the least residues of powers modulo 3763. Suppose that A is as in Exercise 1 and A received from B the ciphertext message 0737 1627. (a) Compute A's deciphering key. (b) Decipher B's message to A