A manufacture has been selling 1900 television sets a week at $390 each. A market survey indicates that for each $30 rebate offered to a buyer, the number of sets sold will increase by 300 per week. i. Find the demand function p(x), where x is the number of the television sets sold per week. p(x)= ii. How large rebate should the company offer to a buyer, in order to maximize its revenue? $ iii. If the weekly cost function is 123500 + 130x, how should it set the size of the rebate to maximize its profit? $