Answer:
3. about 7.48 hours
4. about 1.8892 hours
Explanation:
Both of these questions make use of the relation ...
time = distance / speed
3. time = (965 mi)/(129 mi/h) ≈ 7.48062 h ≈ 7.48 h
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4. time = (612.1 mi)/(324 mi/h) ≈ 1.889198 h ≈ 1.8892 h
(We have rounded the time to sufficient precision so that the distance at the given speed rounds to the number given.)