Which one of the following statements about cost behaviour is true? Select one: Fixed costs per unit vary with the level of activity. Variable costs per unit are not constant within the relevant range. Total fixed costs are not constant within the relevant range. Total variable costs are constant within the relevant range. Pizza Paradise makes and sells only one kind of Pizza; Hawaiian Pizza, which is made with a key ingredient, Pineapple slices. Classify the Pineapple slices used in the making of the Hawaiian Pizzas. Select one: o Direct product cost. O Indirect product cost. Direct period cost. O Indirect period cost