please provide step wise answer.

Example 4: A person bought a car for JD20,000 he payed JD5,000 immediately while the remaining amount will be repaid at 4 equal annual payments, at an annual interest rate of 12%, calculate: l. The value of each installment. 2. If he paid the first two installments but he could not pay the rest of the amount on time agreed upon, so his penalty was to repay the remaining amount in four equal installments, starting in the fifth years after the purchase of the car, find the value of the new installment