A Consumer's Demand for CDs Can Be Represented by a Line

Multiple Choice

A consumer's demand for CDs can be represented by a line with slope -b and intercept a. If the current price of CDs is $P, then the ratio of consumer surplus to total expenditures on CDs equals

A) (a - P) (a - bP) .
B) 1/2(a - P) (a - bP) .
C) D(a - bP) .
D) (a - P) /P.
E) (a/b - P) /(2P) .