Show stoppers is a monopoly provider of ticket services for the concerts and sporting events and their current service charge is $10.00 . in order to attract one more customer, they have to lower their service charge to $9.50 . show stoppers' marginal revenue of this additional customer is:
a. $9.50
b. greater than $9.50.c. less than $9.50.d. between $10.00 and $9.50.

Simon, aged 10, is invited to a classmate's birthday party at an exclusive ski resort on march 15th. the day will include 4 hours of snowboarding, lunch and birthday cake. simon's mother checks a box on the invitation that says "yes, we will attend" and returns it to the classmate's address. unfortunately, they later don't attend the party when simon comes down with the flu. on march 17th, simon's mother receives an invoice in the mail from simon's classmate for $35 that says, "party no-show fee." can simon's classmate collect the fee?