John is repairing the electrical line of his house. As a precautionary measure, he stands on a wooden plank. John uses the wooden plank because wood is
John is repairing the electrical line of his house. As a precautionary measure, he stands on a wooden plank. John uses the wooden plank because wood is
A
An electrical conductor
B
An electrical insulator
C
A heat conductor
D
A heat absorber
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John is repairing the electrical line of his house. As a percautionary measure, he stands no a wooden plank. John uses the wooden plank because wood is
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