John wants to calculate his customers' reaction to a price increase for the milk he sells in his grocery store. What would be the correct formula for him to use? The quantity of milk sold divided by the price of milk. O The percentage change in the quantity demanded for milk, multiplied by the percentage change in price of milk. The quantity of milk sold multiplied by the price of milk. O The percentage change in the quantity demanded for milk, divided by the percentage change in price of milk