A scientist estimates that the mean carbon dioxide emissions per country in a recent year are greater than 150 megatons. You want to test this estimate. To do so, you determine the carbon dioxide emissions for 42 randomly selected countries for that year. The results (in megatons) are shown in the table at the left. Assume the population standard deviation is 816 megatons. At α = 0.06, can you support the scientist’s estimate?

(a) Identify the claim and state H₀ and Ha, 

(b) Find the critical value(s) and identify the rejection region(s), 

(c) Find the standardized test statistic z, 

(d) Decide whether to reject or fail to reject the null hypothesis, and 

(e) Interpret the decision in the context of the original claim.

Transcribed Image Text:

Carbon dioxide emissions (in megatons) 340 76 46 44 75 1617 0.5 0.3 0.5 34 43 0.3 0.7 0.6 0.6 23 11 0.1 0.2 7.6 8.2 26 9.9 2.3 3.4 0.1 472 4.2 4.2 5 0.1 16 113 21 7.2 5 4.1 0.2 45 5.1 175