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 @ $0.71 per hour Variable overhead 3 hours per unit @ $2.09 per hour Actual Costs Total variable cost, $18,100 Total fixed cost, $7,900 The total factory overhead cost variance is

a.$1,798 unfavorable

b.$3,360 unfavorable

c.$4,922 favorable

d.$3,360 favorable