Can i get some guidance with this calculation please??

At the start of the month, a customer owes a credit card company $1000. In the middle of the month, the customer pays $P to the company, where P< $1000.

At the end of the month, the company adds interest at the rate, R, of 3% of the amount still owing. This procedure is repeated in each subsequent month.

a. Find the value of P for which the customer owes $1000 at the end of every month.

b. Find the value of P, for which the whole amount is paid off after the second payment.

c. Assuming that the debt is not paid off after 4 payments, show that the amount still owing at the beginning of the 5th month can be expressed as

$ (1000R^4 - (PR(R^4-1))/R-1 ), R=1.03

d. Show that the value of P for which the whole amount owing is exactly paid off after the nth payment is given by

P = (1000R^n-1 (R-1) ) / (R^n - 1)