To find the temperature at midnight, we start with the temperature at 9:00 AM, which is 17.2°F, and then subtract the change in temperature, which is a decrease of 19.5°F.
Temperature at midnight = Temperature at 9:00 AM - Decrease in temperature
Temperature at midnight = 17.2°F - 19.5°F
Temperature at midnight = 17.2 - 19.5
Temperature at midnight = -2.3°F
Thus, the temperature at midnight is –2.3°F.
The correct answer is D –2.3°F.