Assume that John's cell phone service provider charges $5.00 per month and $0.10 per minute per call. If John's current bill is $50.00, how many calling minutes did John use? A) 500 minutes B) 550 minutes C) 450 minutes D) 400 minutes Nancy was reviewing the water bill for her dog day care and spa and determined that her highest bill, $3, 800, occurred in May when she washed 400 dogs and her lowest bill, $2, 400, occurred in November when she washed 200 dogs. What was the variable cost per dog associated with Nancy's water bill? A) $6.00 B) $12.00 C) $9.50 D) $7.00 Which of the following costs does not change in total despite changes in volume? A) Fixed cost B) Variable cost C) Mixed cost D) Total production cost Costs that have both variable and fixed components are called: A) fixed cost. B) variable cost. C) mixed cost. D) contribution cost. Which of the following costs changes in total in direct proportion to a change in volume? A) Fixed cost B) Variable cost C) Mixed cost D) Period cost Jezebel Company incurred fixed costs of $300,000. Total costs, both fixed and variable, arc $450,000 when 50,000 units are produced. It sold 35,000 units during the year. Calculate the variable cost per unit. A) $9 B) $12 C) $6 D) $3 Pluto Company sold 2,000 units in October at a price of $35 per unit. The variable cost is $20 per unit. Calculate the total contribution margin. A) $70,000 B) $30,000 C) $40,000 D) $20,000