試題詳解

1. When the local used bookstore prices economics books at $20.00 each, they generally sell 70 per month. If they lower the price to $8.00 each, they sell 90. Hence, the elasticity of demand for these economics books is
(A) 3.43, so this store should lower price to raise total revenue.
(B) 3.43, so this store should raise price to raise total revenue.
(C) 0.29, so this store should lower price to raise total revenue.
(D) 0.29, so this store should raise price to raise total revenue.