13. (1 point) A manufacture has been selling 1700 television ets a week at 480 each. A market survey indicates that for each 27 rebate offered to a buyer, the number of sets sold will ncrease by 270 per week. ) Find the demand function p(x), where x is the number of the elevision sets sold per week. (x) ) How large rebate should the company offer to a buyer, in rder to maximize its revenue? ) If the weekly cost function is 136000 + 160x, how hould it set the size of the rebate to maximize its profit