3. Suppose a rm's net investment, I, is a continuous ow: 10s) = as2 2: + 2 where t is years. The capital stock is equal to all accumulated net investment. (3.) Compute the capital stock after 3 years. (1)) Compute the change in capital stock from the beginning of year 5 to the end of year 6. (c) If a firm faces marginal cost of 0'01) = (80.019 + 1), nd average cost. Hint: Average cost = 0