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Answer:</h2>
Variance
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Step-by-step explanation:</h2>
The standard deviation is related to the variance. The standard deviation measures the variation or dispersion of a set of data and is represented by the Greek letter sigma 
, while the variance measures how far a set of numbers are spread out from their average value. The variance is obtained by squaring the standard deviation, so the variance can be found as 
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Define x:
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Let the shorter piece be x.
Shorter piece = x
Longer piece = 6x
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Construct equation:
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x +6x =35
7x = 35
x =5
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Find the length:
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Shorter length = x = 5 feet
Larger length = 6x = 6(5) = 30 feet
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Answer: The shorter piece is 5 feet.
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According to the definition, is a parabola is in the standard form of (x-h)^2<span>=4p(y-k), then the directrix is y=k-p. In this case, the parabola function is x^2=8y, so h=0, p=8/4=2, k=0. Plug the values of h, p, k, into y=k-p, the directrix is y=-2.</span>
