In order to compare the means of two populations, independent random samples of 400 observations are selected from each population, with the following results: (x1 and x2 are sample means)    Sample 1                               Sample 2 X1 = 5,275                              x2= 5,240 S1 = 150                                  S2= 200   Use a 95% confidence interval to estimate the difference between the population means (u1 - u2)    Interpret the confidence interval

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