Can you solve my questions please ? i couldnt do them ?

8. A manufacturer has determined that the marginal-cost function is ac dq 0.003q2 - 0.4q + 40, where q is the number of units produced. If marginal cost is $27,50 when q # 50 and fixed costs are $5000, what is the average cost of producing 100 units? 9. A manufacturer has determined that, for a certain product, the average cost (in dollars per unit) is given by C2q2 - 42q + 228 + 210 where 3 $ 9 $ 12. (a) At what level within the interval 3, 12) should production be fixed in order to minimize total cost? What is the minimum total cost? (b) If production were required to lie within the interval (7,12], what value of q would minimize total cost