(b) Should this confidence interval be used to estimate the mean weight of all oneyearold babies in the United States? Explain. The confidence interval (Choose one) V be used to estimate the mean weight of all oneyearold babies in the United States. should should not Hip surgery: In a sample of 118 hip surgeries of a certain type, the average surgery time was 135.9 minutes with a standard deviation of 22.1 minutes. b) If a 99.5% confidence interval were constructed with these data, would it be wider or narrower than the interval constructed in part (a)? Explain. (Choose one) V than the interval constructed in part (a). narrower The new confidence interval would be Babies: According to a recent report, a sample of 300 oneyearold baby boys in the United States had a mean weight of 255 pounds. Assume the population standard deviation is o : 5.2 pounds