Which of the following statements is false when considering the behavior of a mixed cost within the relevant range? Multiple Choice The total amount of a mixed cost will increase when the level of activity increases. The average mixed cost per unit will increase when the level of activity decreases. The variable portion of a mixed cost causes the total amount of a mixed cost to decrease when the level of activity decreases. The fixed portion of a mixed cost causes the total amount of a mixed cost to remain constant when the level of activity increases.