One unit of

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$($

$$A

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$)$

$$is composed of

$2$

$$units of

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$($

$$B

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$)$

$$and three units of C

$.$

$$Each

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$($

$$B

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$)$

$$is composed of one unit of

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$($

$$F

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$)$

$.$

$\backslash$

$($

$$C

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$)$

$$is made of one unit of

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$($

$$D

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$)$

$,$

$$one unit of

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$($

$$E

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$)$

$,$

$$and two units of

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$($

$$F

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$)$ what is the formula for gross requirement of item F$?$