(Figure: Interpreting a Market Graph) If the Price of Leather

Multiple Choice

(Figure: Interpreting a Market Graph) If the price of leather used to make shoes falls such that the supply of shoes increases by 20 shoes at every price, then the amount of shoes supplied at a price of $60 before the change would be _____ pairs, and after the change, it would be _____ pairs.

A) 30; 50
B) 20; 40
C) 10; 30
D) 40; 60