Using z$=3,$ the control chart limits for this process are$($assume that the historical complaints rate is$$ unknown$)$:

UCL Subscript c $=$

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$13\mathrm{.}35$ complaints per week $($round your response to two decimal$$ places$).$

Part $4$

LCL Subscript c $=$

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$0$ complaints per week $($round your response to two decimal places and if your answer is$$ negative, enter this value as$0).$

Part $5$

$$c$)$ According to the control$$ limits$,$ the process has been

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