John was checking the water bill for his carwash business and determined that the highest bill, $5,100, occurred in July when 2,400 cars were washed and the lowest bill, $3,500, occurred in February when 1,800 cars were washed. What was the variable cost per carwash? A. $1.46 O B. $2.13 C. $2.67 D. $1.94 How do total variable costs behave? A. They will decrease as production decreases within the relevant range. B. They will remain the same as production levels change within the relevant range. C. They will increase as production decreases within the relevant range. OD. They will decrease as production increases within the relevant range