Suppose that messages are numbers between 1 and 1000. Consider the hash function h(M) = ((M mod 91) * 10) mod 73. So, for example, h(99) = ((99 mod 91) * 10) mod 73 = 80 mod 73 = 7. Suppose a digital signature scheme worked as follows. If A wanted to sign a message M, his signature would be EKRA(h(M)), where the encryption is being done with RSA. Is this a good scheme? (a) Give a YES/NO answer. (b) Explain your answer i.e. if you said YES explain why you think this is a good scheme, if you said NO explain why by showing that if you were the bad guy BG and intercepted the message M;EKRA(h(M)), how you would convince B that another message M0 (which you as the BG have generated and which is di erent from M) had actually been signed by A. Illustrate your answer by showing that if M = 101, what would be another number M0 which you could persuade B to accept.