Pulling a rope until it rips in half is the newest strength-training fad. Is it easier to pull against a wall or a friend?
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Just because it looks like all the steps are valid doesn't mean that they are. What went wrong in this "proof"?
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Buoyancy will always bring air bubbles to the surface, but do all bubbles rise at the same rate?
Series 3 of 3
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Calcdoku is a game of logical reasoning. What numbers will successfully fill the grid?
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Some 3D shapes have similar cross-sections. Can you compare how the cross-sections change to identify the solids they come from?
Series 2 of 2
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Paleontologists have found the fossilized tracks of giant bugs around the globe. Why don't we see human-sized bugs today?
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Random sampling allows for thinking about an entire group without looking at every individual.
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