qustion a and b Thanks.

Problem 2 (Pseudorandom Functions) (15 Points) Let F: {0,1}" x {0, 1}" + {0,1}2n be a PRF. One of the following is not a PRF. Which is it? Provide an attack. (a) F (2) F(0||1)||F(1||3) def (b) F1() def F&(1||1)||F#(7||0) le Problem 2 (Pseudorandom Functions) (15 Points) Let F: {0,1}" x {0, 1}" + {0,1}2n be a PRF. One of the following is not a PRF. Which is it? Provide an attack. (a) F (2) F(0||1)||F(1||3) def (b) F1() def F&(1||1)||F#(7||0) le