Problem 2. (a) An n x n matrix K is the encryption matrix for the Hill cipher. Give the encryption formula. (b) The plaintext is (2,5,1,0). Encrypt it (show your work and the ciphertext) using the Hill cipher with the array 3 3 ] 2 11 (c) Find the inverse to the matrix from (b). (d) Explain how to perform the chosen plaintext attack on a Hill cipher that uses a 3 x 3 encryption matrix