Find the present value of the following ordinary annuities (See hint for Problems 4-9):
- $400 per year for 10 years at 10%.
- $200 per year for 5 ears at 5%
- $400 per year for 5 years at 0%.
- Now rework parts a, b and c assuming that payments are made at the beginning of each year, that is, they are annuities due.