Elite Auto Service Station services different makes and models of cars and SUVs. The auto station, to determine the quality of service it provides, conducts a weekly survey of five of its customers. The survey is a 100-point customer satisfaction rating instrument where a perfect score of 100 denotes that the customer is completely satisfied. The following table provides the results of the survey that the auto service station conducted over the past 12 weeks:

1. Construct a mean and a range chart to monitor customer satisfaction at the auto service station using 3σ control limits.

2. Determine whether the manager of this service station is capable of achieving a customer rating score between 90 and 96.

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Customer Rating Score Week 90 96 88 80 92 100 94 82 87 94 3 97 99 78 85 90 60 88 91 93 94 5 89 95 90 84 78 98 90 100 92 84 7 80 98 86 88 96 92 74 89 93 82 88 97 85 90 86 10 93 87 95 97 90 11 74 82 83 79 92 94 12 81 89 99 83