Following trading hours on April $25,2017,$ Costco Wholesale Corporation $($symbol: COST$)$ announced that it would pay a special dividend of $$7\mathrm{.}00$ per share in early May. The ex$-$dividend date for this special dividend was May $8,2017.$ Thus, if you held COST stock at the beginning of May $8,2017,$ you would have been paid the special dividend of $$7$ per share. Otherwise, you would have not received the special dividend. The purpose of this question is to examine the COST price reaction on the announcement date and ex$-$dividend date. e$)$ The top marginal tax rates in $2017$ for dividends and capital gains are both $20$ percent. Based on those numbers, what is the effective dividend tax rate? Why do you think this is different from your answer in part $($d$)?($This difference is most likely related to reasons other than taxes.$)$