The controller has asked a question: The static budget, at the beginning of the month, for Red Deer Compary follows: Static budget Sales volume: 2000 units; Sales price: $50.00 per unit Variable costs: $14.00 per unit: Fixed costs: $25,100 per month Operating income: $46,900 Actual resuits, at the end of the month, follows: Actual results: Sales volume: 1900 units; Sales price: $58.00 per unit Variable costs: $16.5 per unit; Fixed costs: $34,000 per month Operating income: $44,850 Calculate the flexible budget variance for operating income $3600U$3600F$1550F$15,200F