No work needed, only correct solution for part C (round to 2 decimal places):

1.

Test a claim that the mean amount of carbon monoxide in the air in U.S. cities is less than 2.31 parts per million. It was found that the mean amount of carbon monoxide in the air for the random sample of 65 cities is 2.39 parts per million and the standard deviation is 2.11 parts per million. At a = 0.01, can the claim be supported? Complete parts (a) through (e) below. Assume the population is normally distributed. (a) Identify the claim and state H, and He. Which of the following correctly states H, and H? Ho: 2 2.31 Ha: H 2.31 (Type integers or decimals. Do not round.) The claim is the alternative hypothesis. (b) Use technology to find the critical value(s) and identify the rejection region(s). The critical value(s) is/are t= -2.39 . Use a comma to separate answers as needed. Round to two decimal places as needed.) Choose the graph which shows the rejection region. O A. B. O c. O D. - to to t to Q a -to o to O to T - to o to (c) Find the standardized test statistic, t. The standardized test statistic is t = (Round to two decimal places as needed.)In traveling across flat land, you see a mountain directly in front of you. Its angle of elevation (to the peak) is 3.5". After you drive 15 miles closer to the mountain, the angle of elevation is 9 (see the following figure). 3.5 15 mi Not drawn to scale Approximate the height of the mountain. (Round your answer to one decimal place.) 1% mi