You just obtained a credit card. you immediately purchase a digital camera for $160. your credit limit is $4000. let’s assume that you make no payments and purchase nothing more and there are no other fees. the monthly interest rate is 1.42%.

Every month your balance includes the original amount (100%) and the added the monthly interest (1.42%). So each month the balance will be 101.42% of the prior month's balance. Move the decimal point two places to the left to make that into a decimal. 

 
b. 1.0142

What are the options