Answer: The answer is b) mercury.
Explanation:
Mercury can exist both as a solid and a liquid under normal conditions. This is because it has a low melting point of -38.83°C (-37.89°F) and a high boiling point of 356.73°C (674.11°F). Mercury has a low melting point and is a solid at room temperature because its electrons aren't readily shared between its atoms. This is a consequence of mercury atoms containing so many protons and electrons and the way its electrons organize around the nucleus.
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