Refer to question $6-26$ in the Discussion Questions and Problems section at the end of Chapter $6.$

What is the optimal order quantity if the ordering cost were $$20,$ $$30$ and $$40?$

$C_0=$$$20,Q=20,000$

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$C_0=$$$30,Q^{**}=20,000$

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$C_0=$$$40,Q=20,000$

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