Given the demand function: Q = 90 - 2P and the total cost function: TC = 50 + 20Q.
a. Show that the total revenue function is given by the function TR = 45Q - 0.5Q^2.
b. Determine the Marginal Revenue (MR) function, then calculate the marginal revenue value when the total output (Q) is equal to 10.
c. Determine the profit function (π), then determine the level of output that will produce maximum profit. What is the maximum profit?