The standard costs and actual costs for factory overhead for the manufacture of 3,000 units of actual production are as follows:

Standard Costs

Fixed overhead (based on 10,000 hours) 3 hours per unit @ $0.78 per hour

Variable overhead 3 hours per unit @ $2.02 per hour

Actual Costs

Total variable cost, $18,000

Total fixed cost, $8,000

The total factory overhead cost variance is

a. $-180 unfavorable

b. $600 favorable

c. $1,380 favorable

d. $600 unfavorable