With Higher Fuel Costs,airlines Raise Their Average Fare from $0

Multiple Choice

With higher fuel costs,airlines raise their average fare from $0.50 to $1.50 per passenger kilometre and the number of passenger kilometres decreases from 2.5 million a day to 1.5 million a day.What is the price elasticity of demand for air travel when the price is $1 per passenger kilometre?

A) 2
B) 0.75
C) 1.33
D) 50
E) 0.5