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Understands that a variable can be used as a placeholder for a specific unknown (e.g., x + 8 = 13), and as a representative of a range of values (e.g., 4t + 7).

Why Is There a Tidal Bulge Opposite the Moon?

Demonstrate and calculate the reasons for tidal bulges of water on both hemispheres of Earth, due to the Moon.

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Just What is a Logarithm, Anyway?

Before we talk about logarithms, let's think a little bit about graphing.

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