$\"\"$

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Observe the figure:

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The two lengths are $\"\"$ and $\"\"$ .

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The angle is $\"\"$ .

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A is acute and $\"\"$ because $\"\"$ .

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Therefore, one solution exists.

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Law of sines : $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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The sum of the angles in any triangle is $\"\"$ .

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The length of sides $\"\"$ and $\"\"$ .

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The two angles are $\"\"$ and $\"\"$ .

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The remaining angle $\"\"$ .

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$\"\"$

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Law of sines : $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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Therefore, the length of cable need to initital rise is $\"\"$ .

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$\"\"$

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The length of cable need to initital rise is $\"\"$ .