Answer :
-4.2 degrees. What you would do is from 8-12 (midnight) is 4 hours. So it dropped -16.8 degrees in those 4 hours so -16.8 / 4 is -4.2 degrees. So it dropped -4.2 degrees every hour but it was also -4.2 degrees at 9:00 p.m.
The correct answer is 4.2. This is because -16.8 / 4 is -4.2 degrees.
- Hoped this helped! :)
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