how do you get to 36000 U?

Question 16 Frekko Company provided the following information: Standard costs per unit: Variable overhead Fixed overhead 4 mach, hrs @ $6/mach hr 4 mach, hrs. @$10/mach hr Actual units produced 20.000 units Normal capacity in units 21.000 units Actual machine hours 79.000 machine hours Actual variable overhead cost $540,000 Actual fixed overhead cost $810,000 Using the three-variance method, what is the spending variance? $36.000 U $30,000 U $36,000 F $30.000 F