Problem 7. Complete the proof that Pr[B inverts y]>1 by doing the following. (a) Prove that if y/BAD then Pr[B inverts y]=12(n). Deduce that it suffices to show that Pry{0,1}m[y/BAD]>1/2. (b) Prove that Pr(y1,,yk){0,1}mk[A(y1,,yk) wins \& i st yiBAD]. Deduce that Pry{0,1}m[y/BAD]k (c) Complete the proof by showing that if Pry{0,1}m[y/BAD]1/2, then 2n, a contradiction since is non-negligible