Answer and Explanation:
Given:
Actual output = 660,000
Actual labor hours = 360,000 at $9.50 per hour
Standard labor rate = $10 per hour
Standard output hour = 0.5 hour per wheel
Computation:
Labor Variances includes:
1. Labor Cost Variance
2. Labor Rate Variance
3. Labor Efficiency Variance
1. Labor Cost Variance = (SRĂ—SH) - (ARĂ—AH)
Labor Cost Variance = [$10(Actual outputĂ—Standard output hour)] - [$9.5Ă—360000]
Labor Cost Variance = [$10Ă—330,000] - $3,420,000
Labor Cost Variance = $120,000 (Adverse)
2. Â Labor Rate Variance = (SR-AR)AH
Labor Rate Variance = ($10-$9.5)Ă—360,000
Labor Rate Variance = $180,000 (Favorable)
3. Labor Efficiency Variance = (SH- AH)Ă—SR
Labor Efficiency Variance = [(Actual outputĂ—Standard output hour)-360,000]Ă—10
Labor Efficiency Variance = (330,000 - 360,000) Ă—10
Labor Efficiency Variance  = $300,000 (Adverse)