Assume that the production of output is given by Q(K,L) =K⁰.2 L⁰.6, where K is the quantity of capital and L is the quantity of labor (number of workers) . Let P, r, and w be the price of output, rental rate, and wage rate, respectively. If the firm is minimizing costs for a given level of output, which of the following represents the condition that must be satisfied?
a) r/P = 0.6
b) w/P = 0.6
c) w/r = 0.6
d) P/r = 0.6