Consider the plain (i.e., non-padded) RSA public-key encryption scheme.
(a) Encrypt the message m = 12 using the public key pk = (N,e), where N = 35 and e = 3.
(b) Decrypt the cipher-text c = 12 using the secret key sk = (p, q) = (11, 13), where the corresponding public key is pk = (N, e) = (143, 13).