Answer:
$35
Explanation:
Lets start off by finding the labor cost per hour.
Total - Parts = Labor Total
$309.50 - $187 = $122.50
We found out that that the total labor cost is $122.50. But we still don't know the amount per hour. So we have to divide the total labor cost by the amounts of hours worked.
Total Labor Cost / Hours Total = Cost per hour
122.50 / 3.5 = $35
The cost of labor per hour is $35.