please help with a b and c

(Present value of complex cash flows) How much do you have to deposit today so that beginning 11 years from now you can withdraw $6,000 a year for the next 5 years (periods 11 through 15) plus an additional amount of $12,000 in the last year (period 15)? Assume an interest rate of 7 percent. The amount of money you have to deposit today is $ (Round to the nearest cent.) (Present value of annuities and complex cash flows) You are given three investment alternatives to analyze. The cash flows from these three investments are a follows: Investment B $25,000 End of Year 1 2 3 4 5 6 7 A $ 20,000 20,000 20,000 20,000 20,000 $ 20,000 20,000 20,000 75,000 a. What is the present value of investment A at an annual discount rate of 22 percent? (Round to the nearest cent.)