Answer:
8 minutes
Step-by-step explanation:
time = distance/speed
A decrease of 15 mph from 45 mph means the speed on the second segment is 30 mph. Filling in the given values in the above equation, we have ...
... time = (4 mi)/(30 mi/h) = 4/30 h = 8/60 h Ă— (60 min/h) = 8 min