Answer:
what are solving it with??
Answer:
f'(x) = 
Step-by-step explanation:
i) f(x) = 9 / x
ii) f'(x) = 

Answer:
Unit rate of change = -4.2°F/hour
Step-by-step explanation:
Assuming a constant rate of change, a relationship between the change of temperature as a function of time (in hours) can be described as follows:

There is a temperature drop from 12pm to 5pm, which explains the rate of change being negative. This rate means that at every hour that goes by, the temperature drops by 4.2 degrees.