The standard costs and actual costs for direct materials for the manufacture of 2,550 actual units of product are Direct materials Standard Costs 2,550 kilograms $8.90 Actual Costs Direct materials 2,700 kilograms $8.30 The amount of the direct materials quantity variance is Oa. $1.335 favorable Ob. 51,335 unfavorable Oc. $1.068 favorable Od. $1.068 unfavorable