Ruby Compuny produces a chair for which the standard specifies 5 yards of material per urit. The standard price of one yard of material is 59.40 . During the manth, 5 , 600 chairs were manufactured, using 28,700 yards at a cost of \$9.87 per yard. Oetermine the following: Enter favorable variances at negative numbers. . Direct matenals price variance b. Dicect materials quantity variance c. Total direct materials cost variance