The expression 15n + 2(3p) represents the amount Isaiah spent buying gasoline and snacks, where n represents the price of each gallon of gasoline and p represents the cost of each snack that he bought. Which statement is true about the amount Isaiah spent? He spent 6p dollars on gasoline.
He spent n + p dollars in all.
He bought 15 gallons of gasoline.
He bought 6 dollars worth of snacks.