If hiring an extra worker increases a factory's output from 1000 to 1200 units per day, but the factory has to reduce the price of its product from Rs. 25 to Rs. 24 per unit to sell the additional output, the marginal revenue product of the last worker is
If the ___________ firm has zero costs or only has fixed cost, the quantity supplied in equilibrium is given by the point where the marginal revenue is zero.