At zero direct labor hours in a flexible budget graph, the total budgeted cost line intersects the vertical axis at $30,000. At 10,000 direct labor hours, a horizontal line drawn from the total budgeted cost line intersects the vertical axis at $90,000. Fixed and variable costs may be expressed as:
(a)$30,000 fixed plus $6 per direct labor hour variable.
(b)$30,000 fixed plus $9 per direct labor hour variable.
(c)$60,000 fixed plus $3 per direct labor hour variable.
(d)$60,000 fixed plus $6 per direct labor hour variable.