Question #39      You are choosing between two brands of AAA batteries for your graphing calculator.  A package of four Brand E batteries costs $5.50, and a package of four Brand D batteries costs $3.85. What percent of the cost of Brand E batteries did you save by buying a package of Brand D batteries?             A       30%                                         B       70%           C       55%                                         D       38.5%       Question #40    As a waiter in a restaurant, you work 6-hour shifts. You earn $2.50 per hour and get to keep 80% of your tip money. How much tip money do you need to receive per shift to earn a total of exactly $75 before taxes are deducted?             A       $60                                           B       $15           C       $75                                           D       $100     Question #50     Which of these equations describes a relationship in which every real number x corresponds to a nonnegative real number?             A       y = 2x                                       B       y = 2x 2           C       y = 2x 3                                     D       y = -2x