Hank, a calendar-year taxpayer, uses the cash method of accounting for his sole proprietorship. In late December, he performed $21,000 of legal services for a client. Hank typically requires his clients to pay his bills immediately upon receipt. Assume his marginal tax rate is 32 percent this year and will be 37 percent next year, and that he can earn an after-tax rate of return of 4 percent on his investments. a. What is the after-tax income if Hank sends his client the bill in December? b. What is the after-tax income if Hank sends his client the bill in January? Use Exhibit 3.1. (Round your answer to the nearest whole dollar amount.) c. Based on requirement a and b, should Hank send his client the bill in December or January? 4% 5% 6% 7% 8% 9% 10% 11% 12% Year 1 .962 .952 .943 .935 .926 .917 .909 .901 .893 Year 2 .925 .907 .890 .873 .857 .842 .826 .812 .797 Year 3 .889 .864 .840 .816 .794 .772 .751 .731 .712 Year 4 .855 .823 .792 .763 .735 .708 .683 .659 .636 Year 5 .822 .784 .747 .713 .681 .650 .621 .593 .567 Year 6 .790 .746 .705 .666 .630 .596 .564 .535 .507 Year 7 .760 .711 .665 . .623 .583 .547 .513 .482 .452 Year 8 .731 .677 .627 .582 .540 .502 .467 .434 .404 Year 9 .703 .645 .592 .544 .500 .460 .424 .391 .361 Year 10 .676 .614 .558 .508 .463 .422 .386 .352 .322 Year 11 .650 .585 .527 .475 .429 .388 .350 .317 .287 Year 12 .625 .557 .497 .444 .397 .356 .319 .286 .257 Year 13 .601 .530 .469 .415 .368 .326 .290 .258 .229 Year 14 .577 .505 .442 .388 .340 .299 .263 .232 .205 Year 15 .555 .481 .417 .362 .315 .275 .239 .209 .183