Fixed versus variable cost behavior Vanity Chairs Corporation produces ergonomically designed chairs favored by architects. The company normally produces and sells from 5,000 to 8,000 chairs per year. The following cost data apply to various production activity levels.

Required

a. Complete the preceding table by filling in the missing amounts for the levels of activity shown in the first row of the table.

b. Explain why the total cost per chair decreases as the number of chairs increases.