Final answer:
The lowest temperature is 37°F.
Step-by-step explanation:
To find the lowest temperature, we need to subtract the temperature drops from the initial temperature. The temperature starts at 60°F and decreases by 8°F at sunset. This gives us a temperature of 60°F - 8°F = 52°F at sunset. Overnight, it decreases by another 15°F, so the lowest temperature is 52°F - 15°F = 37°F.