A manufacturer estimates that the annual output at a certain factory is given by Q(K,L)= 16 K^0.7 L^0.3 units, where K is the capital expenditure in thousands of dollars and L is the size of the labor force in worker-hours. Suppose that the current capital expenditure is $450000 and the labor level is 680 worker-hours.
a. Find the current marginal productivity of capital QK
b. Find the current marginal productivity of labor QL.