Án SRS of 25 recent birth records at the local hospital was selected. In the sample, the average birth weight was x = 119.6 ounce Suppose the standard deviation is known to be s = 6.5 ounces. Assume that in the population of all babies born in this hospital, the birth weights follow a Normal distribution, with mean m. Based on the 25 recent birth records, the sampling distribution of the sample mean x can be represented by: a. N(119.6, 1.30). O b. N(119.6, 6.5). O c. N(m, 1.30). d. N(m, 6.5).

To compare the dry braking distances from 30 to 0 miles per hour for two makes of​ automobiles, a safety engineer conducts braking tests for 35 models of Make A and 35 models of Make B. The mean braking distance for Make A is 43 feet. Assume the population standard deviation is 4.6 feet. The mean braking distance for Make B is 46 feet. Assume the population standard deviation is 4.5 feet. At α=0.10​, can the engineer support the claim that the mean braking distances are different for the two makes of​ automobiles? Assume the samples are random and​ independent, and the populations are normally distributed.   The critical​ value(s) is/are   Find the standardized test statistic z for μ1−μ2.

For samples of the specified size from the population described, find the mean and standard deviation of the sample meanx. The National Weather Service keeps records of snowfall in mountain ranges. Records indicate that in a certain range, the annual snowfall has a mean of 83 inches and a standard deviation of 14 inches. Suppose the snowfalls are sampled during randomly picked years. For samples of size 49, determine the mean and standard deviation of x A) μ=83; 0x=2 B) μ = 2; σ= 83 Oc C) μ = 83; σ= 14 D) u 14; = 83 =

A nutritionist claims that the mean tuna consumption by a person is 3.6 pounds per year. A sample of 90 people shows that the mean tuna consumption by a person is 3.4 pounds per year. Assume the population standard deviation is 1.11 pounds. At α=0.06​, can you reject the​ claim?