The auto repair shop of Quality Motor Company uses standards to control the labor time and labor cost in the shop. The standard labor cost for a motor tune-up is given below: Job Standard Hours Standard Rate Standard Cost Motor tune-up 2.50 $4.50 $11.25 The record showing the time spent in the shop last week on motor tune-ups has been misplaced. However, the shop supervisor recalls that 160 tune-ups were completed during the week, and the controller recalls the following variance data relating to tune-ups: Labor rate variance $ 423 U Labor spending variance $ 738 U Required: 1. Determine the number of actual labor-hours spent on tune-ups during the week.