Final answer:
The average temperature change per hour when the temperature fell from 0°F to -13°F in 4 hours is approximately -3°F. You find this by dividing the total temperature change by the number of hours (-13°F / 4 hours).
Step-by-step explanation:
The question asks to calculate the average temperature change per hour, given that the temperature fell from 0°F to -13°F in 4 hours. To find the average change, you subtract the final temperature from the initial temperature and then divide the result by the number of hours.
Initial Temperature = 0°F
Final Temperature = -13°F
Total Change in Temperature = Final Temperature - Initial Temperature
= -13°F - 0°F = -13°F
Total Duration = 4 hours
Average Temperature Change per Hour = Total Change in Temperature / Total Duration
= -13°F / 4 hours = -3.25°F per hour
However, since we round to the nearest whole number, the average temperature change per hour is approximately -3°F per hour, which corresponds to option (b).