$\"\"$

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The wight of the nephew is $\"\"$ .

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The force $\"\"$ , where $\"\"$ is mass and $\"\"$ .

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The force that Tommy is using to lift his nephew is:

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$\"\"$

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$\"\"$ .

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Draw a diagram to related situation.

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$\"\"$

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Use the projection formula for work. Since the force vector $\"\"$ that represents Tommy lifting his nephew is parallel to $\"\"$ , $\"\"$ does not need to be projected on $\"\"$ .

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$\"\"$

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The magnitude of the directed distance $\"\"$ is $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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The work that Tommy did to lift his nephew was about $\"\"$ .

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$\"\"$

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The work that Tommy did to lift his nephew was about $\"\"$ .