An engineer has designed a valve that will regulate water pressure on an automobile engine. the valve was tested on 200 engines and the mean pressure was 5.4 pounds/square inch (psi). assume the population standard deviation is 0.8. the engineer designed the valve such that it would produce a mean pressure of 5.5 psi. it is believed that the valve does not perform to the specifications. a level of significance of 0.05 will be used. find the value of the test statistic. round your answer to two decimal places.

Triangle jkl was dilated using the rule dm, 1/3 the image, triangle j’ k’ l’ is the result of the dilation. a.5 units b.7.5 units c.10 units d.12.5 units

Given that ot =5, xt=12, and ox= 13 is xy tangent to circle o at t? explain.

An annual marathon covers a route that has a distance of approximately 26 miles. winning times for this marathon are all over 2 hours. the following data are the minutes over 2 hours for the winning male runners over two periods of 20 years each. earlier period 14 12 15 22 13 10 19 13 9 14 20 18 16 20 23 12 18 17 6 13 recent period 7 11 7 14 8 9 11 14 8 7 9 8 7 9 9 9 9 8 10 8 (a) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the earlier period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks. for more details, view how to split a stem.) minutes beyond 2 hours earlier period 0 1 2 (b) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the recent period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks.) minutes beyond 2 hours recent period (c) compare the two distributions. how many times under 15 minutes are in each distribution