A National Organization Has Been Working with Utilities Throughout the Nation

Multiple Choice

A national organization has been working with utilities throughout the nation to find sites for large wind machines that generate electricity. Wind speeds must average more than 19 miles per hour $( \mathrm { mph } )$ for a site to be acceptable. Recently, the organization conducted wind speed tests at a particular site. Based on a sample of $n = 45$ wind speed recordings (taken at random intervals) , the wind speed at the site averaged $\bar { x } = 19.9 \mathrm { mph }$ , with a standard deviation of $s = 4.5 \mathrm { mph }$ . To determine whether the site meets the organization's requirements, consider the test, $H _ { 0 } : \mu = 19$ vs. $H _ { \mathrm { a } } : \mu > 19$ , where $\mu$ is the true mean wind speed at the site and $\alpha = .01$ . Suppose the value of the test statistic were computed to be $1.34$ . State the conclusion.

A) At $\alpha = .01$ , there is insufficient evidence to conclude the true mean wind speed at the site exceeds $19 \mathrm { mph }$ .
B) At $\alpha = .01$ , there is sufficient evidence to conclude the true mean wind speed at the site exceeds $19 \mathrm { mph }$ .
C) We are $99 \%$ confident that the site does not meet the organization's requirements.
D) We are $99 \%$ confident that the site meets the organization's requirements.