Nicotine in cigarettes. To determine whether the mean nicotine content of a brand of cigarettes is greater than the advertised value of 1.4 milligrams, a health advocacy group tests
H0: ¹ = 1:4
Ha: ¹ > 1:4
The calculated value of the test statistic is z = 2:42.
(a) Is the result significant at the 5% level? Yes
(b) Is the result significant at the 1% level? No
(c) By comparing z with the critical values in the bottom row of Table C, give two numbers that catch the P-value between them.