With its current levels of input use, a firm's MRTS is 3 (when capital is on the vertical axis and labor is on the horizontal axis). This implies: Group of answer choices if it used one more unit of both capital and labor, the firm could produce 3 more units of output. the firm could produce 3 more units of output if it increased its use of labor by one unit (holding capital constant). if the firm reduced its capital stock by one unit, it would have to hire 3 more workers to maintain its current level of output. the firm could produce 3 more units of output if it increased its use of capital by one unit (holding labor constant). the marginal product of labor is 3 times the marginal product of capital.