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The manager of a computer retail store is concerned that their suppliers have been giving them laptop computers with lower than average quality. Their research shows that replacement times for the model laptop of concern are normally distributed with a mean of 3.9 years and a standard deviation of 0.5 years. They randomly select records on 47 laptops sold in the past and find that the mean replacement time is 3.8 years. Assuming that the laptop replacement times have a mean of 3.9 years and a standard deviation of 0.5 years, find the probability that 47 randomly selected laptops will have a mean replacement time of 3.8 years or less. P(X