If the producer pays the price for each of the inputs that is used is equa l to its value of Marginal…

By the product exhaustion theorem (Euler's theorem under constant returns to scale, or at long-run competitive equilibrium where average cost is at its minimum), when a competitive producer pays each input a reward equal to the Value of its Marginal Product (VMP_i = P * MP_i), the sum of payments to all inputs completely exhausts total revenue (sum of VMP_i * X_i = P * Q). Consequently, total economic profit above opportunity cost is zero, meaning the producer earns zero supernormal profit .