The data table contains waiting times of customers at a​ bank, where customers enter a single waiting line that feeds three teller windows. Test the claim that the standard deviation of waiting times is less than 1.9 minutes, which is the standard deviation of waiting times at the same bank when separate waiting lines are used at each teller window. Use a significance level of 0.025. Complete parts​ (a) through​ (d) below. a. Identify the null and alternative hypotheses. Choose the correct answer below.   b. Compute the test statistic.   c. Find the​ P-value of the test statistic.   d. Does the use of the single line appear to reduce the variation among waiting​ times?

An archer’s standard deviation for his hits is six (data is measured in distance from the center of the target). An observer claims the standard deviation is less.a. What type of test should be used?b. State the null and alternative hypotheses.c. Is this a right-tailed, left-tailed, or two-tailed test?

A marketing researcher wants to estimate the mean amount spent per year​ ($) on a web site by membership member shoppers. Suppose a random sample of 100 membership member shoppers who recently made a purchase on the web site yielded a mean amount spent of ​$58and a standard deviation of ​$55.Complete parts​ (a) and​ (b) below. a. Is there evidence that the population mean amount spent per year on the web site by membership member shoppers is different from ​$51​? ​(Use a 0.01 level of​ significance.)   State the null and alternative hypotheses.

Suppose that Kira is measuring the amount of sleep that the residents of Decatur County get per night. She does not know the standard deviation, nor does she know the distribution of the amount of sleep all Decatur residents get. Therefore, she prefers to obtain a large sample. Kira thus enlists the help of her friend, Jadzia, who works for OkHarmony. This popular dating service finds matches for its clients by how they respond to numerous survey questions. Jadzia slips Kira's question into the mix, and from the member database of over a thousand male and female singles, she is able to obtain a sample of 101 responses. The sample mean is 6.62 hours a night with a sample standard deviation of 1.19 hours. There are no outliers in the sample. Kira plans to perform a t-test with an alpha level of α = 0.05 on the hypothesis that Decatur residents get an average of less than 8 hours of sleep per night. Evaluate all of the following five statements as true or false. The sample is a simple…