What is the present value of the following? Use Appendix B as an approximate answer, but calculate your final answer using the formula and financial calculator methods. a. $8,400 in 12 years at 11 percent? Note: Do not round intermediate calculations. Round your final answer to 2 decimal places. b. $17,200 in 6 years at 9 percent? Note: Do not round intermediate calculations. Round your final answer to 2 decimal places. c. $26,800 in 18 years at 10 percent? Note: Do not round intermediate calculations. Round your final answer to 2 decimal places