17. A manufacturer produced mountain bikes. The research department produced the marginal profit (in dollars) function P1=7000.4x 05x5900 where x is the number of bikes produced per month. Compute the increase in profit going from a production level of 250 bikes per month to 900 bikes per month. Set up a definite integral and evaluate it. 19. Given the demand function 3,000 P = DOC) = x find the average price (in dollars) over the demand interval [450, 650]. 18. The total cost (in dollars} of printing 1: dictionaries is 60:) = 30,000 + 153:. Find the average value of the cost function over the interval [0, 700]. 20. Given the supply function 39 = 5(x) = 209032" Find the average price (in dollars} over the supply interval [25, 50]