Zelma buys p pounds of bananas for 40cents per pound. she pays the clerk with a twenty- dollar bill. the clerk subtracts the total cost of the bananas o the twenty-dollar bill to determine the amount of charge to give zelma. which expression represents the amount of change zelma should receive?
A. p-20
B. 20 -40p
C. 20-.40p
D. .40p-20