A department store claims that its average customer satisfaction rating is 28.5. We believe that this rating is too high, so we randomly sample 40 customers and find a sample average of 25.2. If the standard deviation of customer satisfaction for this store is 13.1, what is the probability of observing a sample at least this far below the claimed mean, assuming the claim is true?

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0.9441

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0.4013

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0.0559

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0.2500