you buy 20 cupcakes for $15 and are going to sell them for $2 each. you want to write an expression that represents how much money you will make each day that you sell cupcakes. which of these quantities should be represented with a variable. A the number of cupcakes sold. B the cost of each cupcakes sold. C the number of cupcakes you bought. D the amount of money you spent on the cupcakes