Fixed overhead expenditure variance
$
Budgeted fixed overhead expenditure (4,200 units x $4 per unit) 16,800
Actual fixed overhead expenditure 17,500
Fixed overhead expenditure variance 700 (A)
The variance is adverse because the actual expenditure was higher than the amount budgeted.
Fixed overhead volume variance
$
Actual production at standard rate (5,000 x $4 per unit) 20,000
Budgeted production at standard rate (4,200 x $4 per unit) 16,800
Fixed overhead volume variance 3,200(F)
The variance is favourable because the actual volume of output was greater than the budgeted volume of output.
If you selected an incorrect option you misinterpreted the direction of one or both of the variances.