The following computations of March labor variances for Sam's Supply Company are incomplete. The missing items are labeled (A) through (D). Labor rate variance = 4,800 hours [(A) - $8.50] = $350 favorable Labor efficiency variance = (B) [5,000 hours - (C)] = $(D) Required: (A) In the table below, identify each missing item by name and the missing value. If the missing value is a variance, state whether it is favorable (F) or unfavorable (U). (1) Name of Item Value (2) (3) (4) (B) During March, the supervisor left for vacation without arranging for a replacement. Which variance(s) would have been most affected by this situation?