The human resources director of a large company recently asked her staff to conduct a study of the airline miles traveled by executives of the company during the most recent calendar year. The analyst assigned to the project randomly sampled 25 male executives and 25 female executives. Of particular interest to the HR director is whether males have greater variability in miles flown than females. The statistics available below were computed from the samples. Based on these​ data, what should the HR director conclude if an alpha level equal to 0.01 is​ used? LOADING... Click the icon to view the statistics about the number of miles flown. Males Females Mean Miles 73,262   66,888   St. Deviation Miles 2,568   1,539   Sample Size 25   25   Let sample 1 be males and sample 2 be females. What are the null and alternative​ hypotheses?     A. H0: σ21=σ22 HA: σ21≠σ22   B. H0: σ21≤σ22 HA: σ21>σ22   C. H0: σ21≥σ22 HA: σ21<σ22   D. H0: σ21≠σ22 HA: σ21=σ22 Determine the test statistic.   F=nothing ​(Round to two decimal places as​ needed.) Determine the critical value.   The critical​ F-value is nothing. ​(Round to two decimal places as​ needed.) ▼   Do not reject Reject the null hypothesis. There is ▼   insufficient sufficient evidence to conclude that males have greater variability in miles flown than females.

A science project involves testing the effects of different types of music on plant growth.  A sample of 24 newly sprouted bean plants is obtained.  The plants are randomly assigned to each experimental condition (6 per group). The experimental conditions are:  rock music, heavy metal, country, and classical.  The dependent variable is the height of each plant after 2 weeks.    The ANOVA results are summarized as follows: MSB = 10 and SSW =40. Construct a summary table for this study

In college, talented runners may join a cross-country team. Runners tend to run their best times when they run even splits. Even splits occur when the runners maintain an even pace throughout the race. The cross-country coach wants to estimate the typical variability in his best runner's 1-mile splits. He takes a random sample of 25 of this runner's mile splits and finds that this runner's mean 1-mile split is 5.44 minutes per mile, with a standard deviation of 0.14 minutes per mile. This runner's 1-mile splits follow a normal distribution. (a) Find the chi-square critical values XL² and Xu² to be used in constructing a 95% confidence interval for the true population standard deviation. (Round your answers to two decimal places.) XL²= XU²= (b) Find the 95% confidence interval for the true variability in his best runner's 1-mile splits. (Round your answers to three decimal places.) lower bound and the upper bound

PETROGAS is testing new filters for its motorbikes. One brand of filter (Filter A) is placed in one motorbike, and the other brand (Filter B) is placed in the second motorbike. Random samples of air released from the motorbikes are taken at different times throughout the day. Pollutant concentrations are measured for both motorbikes at the same time. The following data attached represent the pollutant concentrations (in parts per million) for samples taken at 20 different times after passing through the filters. a. Test the hypothesis that the mean for the pollutant concentration for Filter B is greater than 30. Use the 1% level of significance. b. Construct a 95% confidence interval for the difference in mean pollutant concentration, where a difference is equal to the pollutant concentration passing through Filter A minus the passing through Filter B. c. Using the 5% significance level, determine whether there is evidence that mean for the pollutant concentration for Filter A…