Waterway Company's overhead rate was based on estimates of $184,800 for overhead costs and 18,480 direct labour hours. Waterway's standards allow 2 hours of direct labour per unit produced. Production in May was 840 units, and actual overhead incurred in May was $19,000. The overhead budgeted for 1,680 standard direct labour hours is $16,380 ($4,620 fixed and $11.760 variable). (a) Calculate the total, budget, and volume variances for overhead. Total overhead variance Overhead budget variance $ Overhead volume variance $