Answer:
The -15°C temperature of the ice in their snow cones mean that the temperature of that ice is 15° below the freezing point of water.
Explanation:
It is explained that Celsius scale was calibrated based on water. The scientists use 0°C to represent the freezing point of water and subsequently use positive numbers to indicate temperatures above the freezing point of water and negative numbers to indicate temperatures lower than the freezing point of water.
So, a temperature of -15°C simply means that the temperature is 15° lower than the freezing point of water.
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