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Babies: A sample of 25 one-year-old girls had a mean weight of 24.1 pounds with a standard deviation of 4.3 pounds. Assume that the population of weights is normally distributed. A pediatrician claims that the standard deviation of the weights of one-year- old girls is less than 4 pounds. Do the data provide convincing evidence that the pediatrician's claim is true? Use the a = 0.05 level of significance. Part 1 of 5 State the appropriate null and alternate hypotheses. H:5 = 4 H:0