2+9*3^4 My mother put screen time on my phone. And I also can’t delete some apps for some reason so the time doesn’t delete as well. any solutions? (I was on webtoon and r0blox, I’m not supposed to be on them)

The john deere company has found that revenue,in dollars, from sales of heavy-duty tractors is a function of the unit price p, in dollars, that it charges. if therevenue r is r(p)= -1/2p^2 +1900pa)how much revenue will the company generate if they sell 700 tractors? b) how many tractors does the company want to sell to maximize the revenue?