The Russell Company provides the following standard cost data per unit of product: Materials (4 gallons @ $6 per gallon) $24 Labor (3 hours @ $10 per hour) $30 During the period, the company produced and sold 20,000 units incurring the following costs: Materials 82,000 gallons @ $5.90 per gallon Labor 62,000 hours @ $ 9.75 per hour Determine the labor usage variance at "Favorable" or "Unfavorable". Select one: O a $15,500 u ob. $18,000 u O c. $ 20,000 U O d. $19,000 F