Final answer:
The slope of the temperature change is 2.5, as temperature increases by 2.5 degrees Fahrenheit each hour.
Step-by-step explanation:
The temperature at 5:00 am was −10 degrees Fahrenheit. Each hour, the temperature increased by 2.5 degrees. To find the slope in this situation, one should consider how the temperature changes with time. Given that the temperature increases by 2.5 degrees each hour, the slope (rate of change) here is 2.5. Therefore, when plotting this situation on a graph with time as the x-axis and temperature as the y-axis, for every one hour that passes (the run), the temperature increases (rises) by 2.5 degrees Fahrenheit. In this situation, the slope is positive 2.5 because the temperature increased. Therefore, the correct answer is option b) 2.5.