Answer:
4°F
Explanation:
If the temperature fell 36°F in 9 hours, then;
36°F= 9hours
to get the change in temperature in 1 hour, we will say;
x°F = 1 hr
Since we have
36°F= 9hours
x°F = 1 hr
Cross multiply
9x = 1*36
9x = 36
x = 36/9
x = 4°F
Hence the change in temperature each hour is at 4°F