Present Value of an Annuity Find the present value of the following ordinary annuities. Do not round intermediate calculations. Round your answers to the nearest cent. (Notes: If you are using a financial calculator, you can enter the known values and then press the appropriate key to find the unknown variable. Then, without clearing the TVM register, you can "override" the variable that changes by simply entering a new value for it and then pressing the key for the unknown variable to obtain the second answer. This procedure can be used in many situations, to see how changes in input variables affect the output variable. Also, note that you can leave values in the TVM register, switch to Begin Mode, press FV, and find the FV of the annuity due.) a. $400 per year for 10 years at 12%. $ b. $200 per year for 5 years at 6%. C. $400 per year for 5 years at 0%. $ d. Now rework parts a, b, and c assuming that payments are made at the beginning of each year; that is, they are annuities due. Present value of $400 per year for 10 years at 12%: $ Present value of $200 per year for 5 years at 6%: $ Present value of $400 per year for 5 years at 0%:$