Here are summary statistics for randomly selected weights of newborn girls: n= 284, x= 28.4 hg, s =72 hg. The confidence level is 95%. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. ta/2 (Round to two decimal places

Bill Alther is a zoologist who studies Anna's hummingbird (Calypte anna). (Reference: Hummingbirds, K. Long, W. Alther.) Suppose that in a remote part of the Grand Canyon, a random sample of six of these birds was caught, weighed, and released. The weights (in grams) were as follows. 3.7 2.9 3.8 4.2 4.8 3.1 The sample mean is  = 3.75 grams. Let x be a random variable representing weights of hummingbirds in this part of the Grand Canyon. We assume that x has a normal distribution and σ = 0.64 gram. Suppose it is known that for the population of all Anna's hummingbirds, the mean weight is μ = 4.30 grams. Do the data indicate that the mean weight of these birds in this part of the Grand Canyon is less than 4.30 grams? Use ? = 0.10. (a) What is the level of significance? (Enter a number.) State the null and alternate hypotheses. Will you use a left-tailed, right-tailed, or two-tailed test? H0: μ = 4.3 g; H1: μ > 4.3 g; right-tailed H0: μ < 4.3 g; H1: μ = 4.3 g; left-tailed…

Which primary scales do we call ‘categorical data’?   a. Interval, ordinal   he probability of making a type I error is indicated by the ________.   a. p-value   b. power of a test   c. incidence of difference   d. test statistic

A new vaccination is being used in a laboratory experiment to investigate whether it is effective. There are 279 subjects in the study. Is there sufficient evidence to determine if vaccination and disease status are related? Vaccination Status Vaccinated Not Vaccinated Total Diseased Not Diseased Total 54 87 71 192 125 279 33 121 154 Step 4 of 8: Find the value of the test statistic. Round your answer to three decimal places. Copy Data

Researchers studied the mean egg length (in millimeters) for a bird population. After taking a random sample of eggs, they obtained a 95% confidence interval of (45,60). What is the value of the margin of error? Choose the correct answer below. A. 15 mm B. 52.5 mm O c. 7.5 mm O D. 1.96