Zumba Classes Sell 20 Participant Spots at a Price of $4.50

Multiple Choice

Zumba classes sell 20 participant spots at a price of $4.50 each.When the instructor raised the prices to $5.50,10 people attended the class.From the midpoint method,the price elasticity of demand for Zumba is

A) -0.50.
B) -3.33.
C) -2.50.
D) 0.20.
E) -0.20.