Answer the given questions:

Question: Alice and her brother, Bob, are can't agree on the main course for their family Christmas dinner.

Alice wants a ham and Bob wants a turkey. Alice lives in Dallas and Bob lives in Atlanta, so they decide to use cryptography to perform a "coin flip" over the phone.

Here is the protocol that they use.

- Alice picks a secret bit, b ? {0, 1}.

- Alice picks a secret key, k, and use a block cipher to compute c = Ek(m) where m is b padded with random bits to the correct block length (the first bit of m is b).

- Alice reads the bits of c to Bob over the telephone.

- Bob tries to guess the value of b. Call his guess b'. Bob tells Alice his b' over the phone.

- Alice reads k to Bob. Bob decrypts c to recover b (the first bit of m).

If b' = b, Bob wins and they have turkey, otherwise they have ham.

Question 1. Describe how Alice can cheat.

Question 2. Describe how an one­way hash function can prevent this attack.

You have to satisfy the requirements specified in the instruction.