Let x be a random variable representing dividend yield of bank stocks. We may assume that x has a normal distribution with = 2.1%. A random sample of 10 bank stocks gave the following yields (in percents). 5.7 4.8 6.0 4.9 4.0 3.4 6.5 7.1 5.3 6.1 The sample mean is x bar = 5.38%. Suppose that for the entire stock market, the mean dividend yield is = 4.6%. Do these data indicate that the dividend yield of all bank stocks is higher than 4.6%? Use = 0.01. What is the level of significance? (Enter a number.) Compute the z value of the sample test statistic. (Enter a number. Round your answer to two decimal places.) Find (or estimate) the P-value. (Enter a number. Round your answer to four 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 x bar = 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 = 0.64 gram. Suppose it is known that for the population of all Anna's hummingbirds, the mean weight is = 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. What is the level of significance? (Enter a number.) Compute the z value of the sample test statistic. (Enter a number. Round your answer to two decimal places.) (c) Find (or estimate) the P-value. (Enter a number. Round your answer to four decimal places.)