Chelsa Manufacturing Co.'s static budget at 5,000 units of production includes $40,000 for direct labor and $5,000 for variable electric power. Total fixed costs are $23,000. At 8,000 units of production, a flexible budget would show

a. variable costs of $64,000 and $28,000 of fixed costs

b. variable costs of $72,000 and $23,000 of fixed costs

c. variable and fixed costs totaling $107,000

d. variable costs of $64,000 and $23,000 of fixed costs