Use the unpaid balance method to find the finance charge on the credit card account. The last month's balance and any other transactions are given. Round to two decimal places. Month: May (31 days) Previous month's balance: $960 Interest rate: 21%

A. $32.80 B. $13.98 C. $10.34 D. $798.80

Transaction May3:made payment of $310 May 12:charged $109 for rental car May21:charged $89 for museum tickets May 29:returned $66 for camera