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If an electric train is traveling south, which way is the smoke going?

North None Insufficient information No specific direction

Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

Master advanced concepts through explanations,
examples, and problems from the community.

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by Kushal Patankar

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