A. The digital cash protocol contains a step in which Alice uses a bit commitment protocol. What bits exactly is she committed to?

B. Describe in a little more detail how the use of the bit commitment protocol would work. What does Bob send Alice? What does Alice then send Bob? What does she keep secret from Bob?

C. When does the verification part of the Bit commitment protocl take place?

Describe how a criminal, Alice, might use digital cash to commit extortion.

In particular describe how a ompletely safe pay-off could be arranged.

What Alice send her victim (Victor)?

What does he then do?

Hint: Exexuting the payoff will require publishing something in the newspaper. What is published and what does Alice do with the information?