i need the solution in steps

9. Assume cipher block width 64 bit and key size 80 bit and C1=E(P1,K) a) How many different messages can be generated using the cipher block? b) If you encrypt P1 under all possible keys, how many all possible ciphertexts will be produced? c) Compare the results in a) and in b)? Explain d) How can we overcome the problem identified in c)