10 percent of customers visiting a convenience store are interested in purchasing bubble gum. Each of those customers who are interested has the demand given by P = 20 - 4Q, or Q = 5 - 0.25P, where P is in cents and Q is in individually wrapped pieces of bubble gum.

a. (2.5 pts) In the space below, choose an appropriate scale and plot the demand of a representative consumer.

(If this task gives you trouble, just sketch a straight line and use it in answering the questions that follow.)

b. (2 pts) The marginal cost of supplying each piece of bubble gum is 4 cents. Plot the marginal cost on the same graph below.

**Graph appears here within review**