Lisa is choosing between three alternatives: a) working at her job that pays 60 dollars; b) writing a term paper which she values at 40 dollars; or c) going out with a friend, which she values at 80 dollars. the opportunity cost of writing the term paper is: 0 dollars. 80 dollars. 20 dollars. 140 dollars.

Suppose that a paving company produces paved parking spaces (q) using a fixed quantity of land (t) and variable quantities of cement (c) and labor (l). the firm is currently paving 1,000 parking spaces. the firm's cost of cement is $3 comma 600.003,600.00 per acre covered (c) and its cost of labor is $35.0035.00/hour (w). for the quantities of c and l that the firm has chosen, mp subscript upper c baseline equals 60mpc=60 and mp subscript upper l baseline equals 7mpl=7. is this firm minimizing its cost of producing parking spaces?