1. (3 pts) Compute the XOR of the following bit strings expressed in hexadecimal, also giving the result in hexadecimal. You may wish to convert to binary first. a. ff ff ff ff de ad be ef b. 88 88 44 44 0 77 77 bb bb c. ca fe fa ce 10 45 57 ce 2. (3 pts) Explain why the one-time pad, if used correctly, is not susceptible to a brute-force attack