You have been pricing an MP3 player in several stores. Three stores have the identical price of $300. Each store charges 24 percent APR, has a 30-day grace period, and sends out bills on the first of the month. On further investigation, you find that store A calculates the finance charge by using the average daily balance method, store B uses the adjusted balance method, and store C uses the previous balance method. Assume you purchased the MP3 player on May 5 and made a $100 payment on June 15.

What will the finance charge be if you made your purchase from:

a. store A?
b. store B?
c. store C?