The Static Budget,at the Beginning of the Month,for Redwyne Company

The static budget,at the beginning of the month,for Redwyne Company follows: Static budget:
Sales volume: 2,000 units; Sales price: $50.00 per unit
Variable costs: $13.00 per unit; Fixed costs: $25,200 per month
Operating income: $48,800
Actual results,at the end of the month,follows:
Actual results:
Sales volume: 1,800 units; Sales price: $58.00 per unit
Variable costs: $16.00 per unit; Fixed costs: $33,600 per month
Operating income: $42,000
Calculate the flexible budget variance for variable costs.

A) $28,800 U
B) $600 U
C) $5,400 U
D) $23,400 F