Consider the Following Equations for the Demand for Good A,where

Multiple Choice

Consider the following equations for the demand for good A,where Q_A denotes quantity demanded,P_A denotes price,and M denotes income: 1.Q_A = 120 + 3.5 P_A + 14M
2.Q_A = 120 - 3.5 P_A + 14M
3.Q_A = 120 - 3.5 P_A - 14M
Which of these equations represents a downward-sloping demand curve for an inferior good?

A) 1 only
B) 2 only
C) 3 only
D) 1 and 2
E) none of the equations