Find the present value of $400 due in the future under each of these conditions:

1. 9% nominal rate, semiannual compounding, discounted back 9 years. Do not round intermediate calculations. Round your answer to the nearest cent.

   $

2. 9% nominal rate, quarterly compounding, discounted back 9 years. Do not round intermediate calculations. Round your answer to the nearest cent.

   $

3. 9% nominal rate, monthly compounding, discounted back 1 year. Do not round intermediate calculations. Round your answer to the nearest cent.

   $

4. Why do the differences in the PVs occur?