Answer:
he flipped his ruler and is now using a different unit of measurement
10
Step-by-step explanation:
$150 minus the base pay of $30 is $120. Divide this by the $12 he makes each delivery. 120/12=10
1, 2, 3, 4, 6, 9, 12, 18, 36
Hope it helps.
Please mark it as Brainliest.