Can you please help me with my math problem about depreciation and compound interest?

Question

I have to calculate the amount of money I will earn/lose at the given rate over the given time.

a) You spend $20,000 on a new car, which will depreciate at a rate of 7.5% per year over the next ten years.

b) You pay off your credit cards with the $20,000, which charge 7.5% interest compounded monthly, assume it takes 10 years to pay them off.

Any help would be appreciated.

Answer 1

A) take the value, subtract 7.5% for year one, take that number, subtract 7.5% for year two. the beginning value minus the ending is how much you "lost".

B)