only (a)

Chapter 2: Problem 2 Previous Problem Problem List Next Problem (1 point) A cryptography student has accidentally used the same keystream to encrypt two different messages, M and M2. We know that the ciphertexts are C = 0x0ac83f62826db967 and C2 = 0x36c4a5e29e f3d08c. We also happen to know that M1 = 0xc8d3520cd87b962f. a) What is M2 in hexadecimal? Please give your answer a leading Ox and use lowercase letters only. b) What is the keystream? Please give your answer a leading Ox and use lowercase letters only. Hint: These are all 8 byte numbers and will fit in an unsigned long type on most systems. Chapter 2: Problem 1 Previous Problem Problem List Next Problem (1 point) Consider the hex strings A=0x 148c0a30ac5cbc83 and B=0x773653ca8f06660a. a) What is A B in hexadecimal? Please give your answer a leading Ox and use lowercase letters only. Make sure you use exactly 16 hex digits (which may involve typing in leading zeros). hexadecimal: 1 b) Suppose that A was generated uniformly at random from all 8 byte strings. What is the probability that the second binary digit of A is 1? 0.5 c) Suppose that A was generated uniformly at random from all 8 byte strings. What is the probability that the second binary digit of A B is 1? 1.5