$\"\"$

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To find the value of $\"\"$ .

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The number of permutations formula: $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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The fundamental counting principle $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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The solution is 35280.