21. Accumulate P100,000 for 15 years if the interest rate is 8% compounded quarterly for the first ten years and 9% compounded monthly for the remaining five years. Find the compound amount at the end of 15 years. 22. Find the compound amount at the end of eight years if P40,000 is invested at 8.5% compounded monthly for the first two years and at 6 1/2 % compounded quarterly for the remaining years