The Crawley Manufacturing Company's costing system has two direct-cost categories: direct materials and direct manufacturing labor. Manufacturing overhead (both variable and fixed) is allocated to products based on standard direct manufacturing labor hours (DLH). At the beginning of 2021, Crawley adopted the following standards for its manufacturing costs:

	Input	Cost Per Output Unit
Direct materials ..............................	3 pounds at $5 per pound	$ 15.00
Direct manufacturing labor ................	5 hours at $15 per hour	75.00
Manufacturing overhead:
Variable .......................................	$6 per DLH	30.00
Fixed .........................................	$8 per DLH	40.00
Standard manufacturing cost per output unit		$160.00

The denominator level for total manufacturing overhead per month in 2021 is 40,000 direct manufacturing labor hours. Crawley's flexible budget for January 2021 was based on this denominator level. The records for January indicated the following:

Direct materials purchased ...................................	25,000 pounds at $5.20 per pounds
Direct materials used ................................................	23,100 pounds
Direct manufacturing labor ..................................	40,100 hours at $14.60 per hour
Total manufacturing overhead (variable and fixed) ......	$600,000
Actual production ...............................................	7,800 output units

Compute the variable manufacturing overhead efficiency variance for January 2021.

	a.	$7,600 unfavorable.
	b.	$6,000 favorable.
	c.	$5,000 favorable.
	d.	$6,600 unfavorable.