The standard costs and actual costs for factory overhead for the manufacture of 2,600 units of actual production are as follows:

Standard CostsFixed overhead (based on 10,000 hours)3 hours per unit @ $0.78 per hourVariable overhead3 hours per unit @ $1.96 per hour

Actual CostsTotal variable cost, $18,100Total fixed cost, $8,200

The amount of the variable factory overhead controllable variance is

a.$2,812 favorable

b.$0

c.$2,250 favorable

d.$2,812 unfavorable