Microeconomics 18th Edition by Campbell McConnell, Stanley Brue, Sean Flynn

Exercise 7

Suppose P₄ is $10, P 5 is $15, Q₄ is 8 units, and Q 5 iS₁0 units. This firm's:
a. supply curve is elastic over the Q₄ - Q 5 range of output.
b. supply curve is inelastic over the Q₄ - Q 5 range of output.
c. total revenue will decline if price rises from P₄ to P 5.
d. marginal-cost curve will shift downward if price falls from P 5 to P₄.