Ruby Company produces a car for which the standard specifies 3 yards of material per unit. The standard price of one yard of material is $13.90. During the month 6.200 chains were manufactured using 18,400 yards at a cost of $14.73 per yard. Determine the following: Enter favorable variances as negative numbers, a. Direct materials price vanance b. Direct matenals quantity wariance C. Total direct materials cost variance $