4. The position function of an object is given by 30) = Zt' 12?2 + 301' + 8. where time, t, is in seconds and distance, .9. is in metres. What is the object's acceleration at f = l? 5. The demand function for a product is given by p(x) = 10 000 0.05:3, where x is the number of units of the product sold and p is the price, in dollars. What is the marginal revenue when 130 units of the product are sold