Use the following table to answer the following questions. Price of Quantity demanded when the Quantity demanded when the T-shirts average income is $25 000 average income is $30 000 4 2000 3000 1700 2800 6 1300 2500 800 2000 a) Explain in your own words (not the textbook definition) what income elasticity of demand is b) Calculate the price elasticity of demand when the price of a T-shirt rises from $4 to $5 and the income is $30 000. c) Calculate the income elasticity of demand when the price of the average income rises from $25 000 to $30 000 and the price of a T-shirt is $7