8) Preble Company manufactures one product. Its variable manufacturing overhead is applied to production based on direct labour-hours, and its standard costs per unit are as follows:

Direct materials: 5 kg at $8.00 per kg	$	40.00
Direct labour: 2 hours at $14 per hour		28.00
Variable overhead: 2 hours at $5 per hour		10.00
Total standard cost per unit	$	78.00

The company planned to produce and sell 25,000 units in March. However, during March the company actually produced and sold 30,000 units and incurred the following costs:

1. Purchased 160,000 kg of raw materials at a cost of $7.50 per kg. All of this material was used in production.
2. Direct labour: 55,000 hours at a rate of $15.00 per hour.
3. Total variable manufacturing overhead for the month was $280,500.

6. What is the labour efficiency variance for March? (Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance.).)