Imagine that two friends, Manuel and Curtis, each buy an iPod touch for $$320,$ and pay with

a credit card. When this happens, the credit card company pays Apple, and the friends

become indebted to the credit card company. For every year they don't pay back the debt,

the company charges them interest: a percentage of what they owe. The interest rate is

called an annual percentage rate $($APR$),$ while the amount owed is called a balance.

Calculate how much each person would owe over time if neither made any payments to the

credit card company, assuming interest is calculated once per year.