A firm has just decreased its price by 20 percent over last year's price, and it found that quantity sold increased by 15 percent. a. What is its

A firm has just decreased its price by 20 percent over last year's price, and it found that quantity sold increased by 15 percent.

a. What is its price elasticity of demand?

Instructions:

The price elasticity of demand is ________.

b. What additional information would you search for before you did your calculation?

a)I would check to see if consumer tastes or expectations had changed.

b)I would check to see if income had changed.I would check to see if the prices of complements and substitutes had changed.

c)I would check to see if taxes or subsidies had changed.

d)I would check all of the above to make sure that all other things remained constant.