A representative firm operates in a competitive market, taking the real wage rate, w, as given. Its production function is Y =zK0.5 (Nd)0.5, where Y is the output of consumption goods, K is the exogenous capital stock (assume zero rental price), Nd is the labor input, and z is the total factor productivity. Assume that z = 4, K = 9, and w = 3. The firm's optimal demand for labor and profits are and, in order. Choose the correct one. 1,9 O 1, 12 4, 12 4, 24