Answer:
5ºF per hour decrease
Explanation:
Given that the temperature in Fairbanks, Alaska, fell 10 degrees in 2 hours
For finding average we normally divide the total by number of units
Here change in temperature for 2 days is given as -10 degrees (negative sign is used to denote decrease)
For 2 days change in temperature = -10 degrees F
Hence average change in temperature = change for one day
= -10/2 = -5 degrees F
So answer is 5ºF per hour decrease