The risk and return components of the efficient frontier are computed for a specific time period, usually one year.

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Non-permanent residents apply for and receive only time-limited residency visas (usually one to three years).

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One of the few is that kindness usually cultivates connection, something we yearn for in a time-pressed, ear-to-the- cell-phone culture.

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The tricky part is that usually, one reason companies use backup tapes is the ability to archive backup tapes off-site for extended periods of time.

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In all of these species, the mothers usually have their babies one at a time, and those offspring are dependent on at least one of their parents for several years after birth.

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