Montgomery Company has developed the following flexible budget formulas for its four overhead items:

		Variable rate per
Overhead item	Fixed cost	direct labor hour
Maintenance	$10,000	$ 3.00
Power	$ 1,500	$ 0.30
Indirect labor cost		$12.00
Equipment lease	$ 7,000
Total	$18,500	$15.30

Montgomery normally produces 15,000 units (each unit requires 0.30 direct labor hours); however this year 19,000 units were produced with the following actual costs:

Overhead item	Actual costs
Maintenance	$14,000
Power	$ 2,200
Indirect labor cost	$70,000
Equipment lease	$ 7,000
Total costs	$93,200

Calculate the variance for maintenance using an after-the-fact flexible budget.

a.$11,000 U

b.$13,000 U

c.$13,100 F

d.$1,000 F

e.None of these choices are correct.

Please show step by step and formulas. It is not C, D, or E.