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

	Standard Costs
Fixed overhead (based on 10,000 hours)	3 hours per unit at $0.73 per hour
Variable overhead	3 hours per unit at $1.95 per hour
Actual Costs
Total variable cost, $18,200
Total fixed cost, $7,900

The variable factory overhead controllable variance is

a.$2,990 favorable

b.$2,392 favorable

c.$0

d.$2,990 unfavorable