1. A Bitcoin payment service might receive thousands of payments from various users near-simultaneously. How can it tell whether a particular user Alice who logged into the payment service website and initiated the payment protocol actually made a payment or not?
2. Should an advertisement be treated as an offer rather than an invitation to make an offer? Why or why not?
3. Please describe the reasons for having a totally anonymous means of accessing the internet. Please also discuss the dangers of that same internet.