Billings Billiard Equipment makes pool balls. This past month, Billings made 32,000 pool balls. Billings' standard hours to make each pool ball is 0.15 hours and its standard labor rate is $16.00 per hour. If it took Billings 4,500 hours to make these balls at a labor cost of $67,500, what was their Labor Efficiency Variance, and is it favorable or unfavorable? a.) $4,800 Favorable b.) $9,300 Unfavorable c.) $3,000 Unfavorable d.) $4,500 Favorable