Consider the following hypothetical demand schedule for "Tammy Fay" brand Mascara:

Qd= 600 - 16 P

WhereQdrepresents quantity demanded in pounds andPis the price in dollars.

(a) Based on this demand schedule, set up a graph (using excel) of the demand curve and the corresponding total revenue curve (with quantity on the horizontal axis).

(b) Calculate the price elasticity (using the point elasticity formula) of demand at quantities demanded of 500, 400, 300, 200 and 100.