To determine which city is warmer after 5 hours and the difference in their temperatures, we can calculate the temperature in each city after 5 hours.
For City A:
- Initial temperature = 70°F
- Temperature change = −5°F per hour
- After 5 hours, the temperature change will be: \[ 5 , \text{hours} \times (-5 , \text{F/hour}) = -25°F \]
- Temperature in City A after 5 hours: \[ 70°F - 25°F = 45°F \]
For City B:
- Initial temperature = 70°F
- Temperature change = −3°F per hour
- After 5 hours, the temperature change will be: \[ 5 , \text{hours} \times (-3 , \text{F/hour}) = -15°F \]
- Temperature in City B after 5 hours: \[ 70°F - 15°F = 55°F \]
Now, we compare the temperatures of both cities after 5 hours:
- City A: 45°F
- City B: 55°F
City B is warmer than City A. The difference in temperature between the two cities is: \[ 55°F - 45°F = 10°F \]
Thus, the correct response is: City B is warmer by 10°F.