The marginal product of labor can be illustrated geometrically as the: a. slope of the total product curve with respect to labor. b. slope of the total product curve with respect to capital. c. slope of a chord from the origin out to the total product curve at the specified level of labor. d. inverse of the slope of a chord from the origin out to the total product curve at the specified level of labor. e. slope of the total product curve with respect to labor divided by the slope of the total product curve with respect to capital.