A retirement benefit of $12,000 is to be paid every 6 months for 25 years at interest rate of 7% compounded semi-annually. Find (a) the present value to fund the end-of-period retirement benefit. (b) the end-of-period semi-annual payment needed to accumulate the value in part (a) assuming regular investments for 30 years in an account yielding 8% compounded semi-annually