Final answer:
Substance C, with a melting point of 11°C and a boiling point of 181°C, would be a liquid at 100°C. This is because the substance is in its liquid state when the temperature is between its melting and boiling points.
Step-by-step explanation:
In a matter of determining which substance would be a liquid at 100 degrees Celsius, we must refer to the given melting and boiling points for each substance. A substance is in liquid state when its temperature is between its melting and boiling points. Here, if we check all the substances, Substance C which has a melting point of 11 C and boiling point of 181 C, would be in a liquid state at 100 C since it lies between its melting and boiling points. The other substances are not in their liquid state at 100 C because the temperature does not fall between their melting and boiling points.
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