Please answer question 14,15 and 16

Question 14 Not yet answered Marked out of 1.00 P Flag question Let E be the encrypted version of a message M that was sent to you by using your public key n, k (with rn being the prime product and k being the coprime of the totient. j is your private key How do you decrypt this message? Select one: 0 a. M-E, (mod k) CM-E (mod n) e. M- E* (mod n) Question 15 Not yet answered Marked out of 1.00 Which one of the following is the characteristic polynomial of the recurrence relation S(k) = 3S(k-1) + 6S(k-2)-85(k-3)? Select one: O a3+3x2 +6-8 P Flag questionb.32 6x -8 ?c.rs _ 3r2-6r + 8 e.338r Question 16 Not yet answered Marked out of 1.00 Let S(k) = 6S(k-1) + 25 and S(0)--4. Which one of the following is a solution for S(k) for all k Select one: P Rlag questionb.S()2-5 d.S(k)-6-5 e.S(k) 32