A store uses the expression –2p + 50 to model the number of backpacks it sells per day, where the price, p, can be anywhere from $9 to $15. Which price gives the store the maximum amount of revenue, and what is the maximum revenue? (Revenue = price mc023-1.jpg number of backpacks.) $9.00 per backpack gives the maximum revenue; the maximum revenue is $32.00. $12.00 per backpack gives the maximum revenue; the maximum revenue is $312.00. $12.50 per backpack gives the maximum revenue; the maximum revenue is $312.50. $15.00 per backpack gives the maximum revenue; the maximum revenue is $20.00.