Write an expression for the following problem, and then use the expression to solve the problem: You own a lunch truck that sells pizza slices and drinks. You charge $4 per slice and $3 per drink. Write an expression that could be used to calculate your total revenues from selling P slices of pizza and D number of drinks. If your average customer order is 4 slices of pizza and 2 drinks, what is the dollar size of your average order? O $14.50 $20.50 $9.00 $13.00 $22.00 $12.00 O $13.50 O $7.00 O $16.50 $21.00