Final answer:
The overall change in temperature over a 45-hour period, with a decrease of 28°F per hour, is -1260°F. Since the decrease in temperature is consistent, we multiply the decrease rate by the period, which leads us to option A being the correct answer.
Step-by-step explanation:
The question asks for the overall change in temperature over a period of 45 hours, with a consistent decrease at a rate of 28°F per hour. To calculate the total change, you need to multiply the rate of temperature decrease by the total number of hours.
Total change in temperature = Rate of temperature decrease × Period (in hours)
Total change in temperature = 28°F/hour × 45 hours
Total change in temperature = 1260°F
Since the temperature is decreasing, the overall change should be expressed as a negative value, which gives us -1260°F. Therefore, option A, -1260°F, best represents the overall change in temperature over this time period.