1. The unpaid balance at the start of a? 28-day billing cycle was ?$997.81. A ?$6,000 purchase was made on the first day of the billing cycle and a ?$100 payment was credited to the account on day 21. How much interest will be charged at the end of the billing? cycle? Assume that the annual interest rate on a credit card is 26.16?% and interest is calculated by the average daily balance method.