Suppose you are advising an industry association on the predicted effects of a price change on quantity demanded and total expenditure on their product. The current price is $1.00 per unit, and quantity demanded is 2500 units per day. Based on extensive empirical studies, you know that price elasticity of demand for the product is 0.5. If the price increases to $2.00 per unit, what is the predicted percentage change in quantity demanded? Will total expenditure increase or decrease? (Remember to use the averaging method to calculate the percentage change in price.)