That school likens its single-variable calculus MOOC to an Advanced Placement course for high-school students.

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The single strongest variable in Google rankings is the number and authority of sites that link to a posting.

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Some palaeontologists see a single, variable species called Homo habilis.

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Furthermore, we look at each variable by single, one-third plan, half plan, and full ticket plans.

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Instead, it is the single most important budgetary variable because it affects the size of the tax base and the amount of government spending linked to the level of employment.

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