$\"\"$

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(a) $\"\"$ .

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Traingle law:

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If $\"\"$ and $\"\"$ from a triangle, then $\"\"$ .

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$\"\"$ .

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$\"\"$

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(b) $\"\"$ .

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The resultant vector is $\"\"$ .

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$\"\"$

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(c) $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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The resultant vector is $\"\"$ .

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$\"\"$

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(d) $\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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(a) $\"\"$ .

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(b) $\"\"$ .

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(c) $\"\"$ .

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(d) $\"\"$ .