$\"\"$

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(a)

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The function is $\"\"$ .

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Power rule of the integrals : $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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Therefore, $\"\"$ .

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$\"\"$

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(b)

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The function is $\"\"$ .

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Find the value of $\"\"$ when $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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Therefore, the value of $\"\"$ .

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$\"\"$

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(c)

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How far from the ground is the phone after $\"\"$ of falling.

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Substitute $\"\"$ and $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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Therefore, the distance from the ground is the phone after $\"\"$ of falling is $\"\"$ .

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$\"\"$

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(a) $\"\"$ .

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(b) The value of $\"\"$ .

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(c) The distance from the ground when the phone after $\"\"$ of falling is $\"\"$ .