Final answer:
The difference between the temperatures is 2 degrees.
Step-by-step explanation:
The difference between the temperatures is calculated by subtracting the initial temperature from the final temperature. In this case, the initial temperature at 6:00 was 9 degrees below zero and it dropped 11 degrees below zero at 8:00. To find the difference, we subtract the initial temperature from the final temperature: (-11) - (-9) = -11 + 9 = -2 degrees. So, the difference between the temperatures is 2 degrees.