Two variable inputs, labor (L) and materials (M), are utilized to produce output. Company's current level of output: CL = $10 / unit, MPL = 25 CM = $2 / unit, MPM = 4 (!) Decide whether the firm is operating efficiently, given that its objective is to minimize the cost of producing the given the level of output (2) Decide what changes (if any) in the relative proportions of labor and materials are needed to operate efficiently.