The purchase of a new car requires P100,000 down payment and the balance to be paid at P300,000 after two years and P600,000 after five years. The rate of interest is 18% compounded monthly. a. Find the present worth of the car. b. Find the lump sum payment if the car is paid after 5 years. c. With a down payment of P100,000 and monthly interest of 1.50%, find the monthly amortization for the 5 years.