1. Recovering a Quantity from it Rate of Change A. The gross domestic product (GPD) of a country of a country is $78 billion and growing at the rate of 4.4t-/ billion dollars per year after t years. Find a formula for the GPD after 7 years. B. A chemical plant is adding pollution to a lake at the rate of 40t3 tons per year, where t is the number of years that the plant has been in operation. Find a formula for the total amount of pollution that will enter the lake in the first t years of the plant's operation [Hint: Evaluate C so that no pollution has been added at time t=0} C. A company's marginal cost function is MC = 21x4/3 - 6x/2 + 50, where x is the number of units and the fixed costs are $3000. Find the cost function by integrating the marginal cost. Use the fixed cost to evaluate the arbitrary constant. Jar