12. The SAT scores of entering freshmen at a certain university have mean 1215 and standard deviation 110. A random sample of 100 freshmen is taken and x, the sample mean of their SAT scores, is computed. The probability that x less than 1190 is (A) 0.0116 (B) 0.1335 (C) 0.4090 (D) 0.4562 (E) 0.1628

17. The nicotine content in cigarettes of a certain brand is normally distributed, with mean (in milligrams) and standard deviation $\sigma = 0.1$. The brand advertises that the mean nicotine content of its cigarettes is 1.5, but measurements on a random sample of 100 cigarettes of this brand give a mean of $\overline{x} = 1.53$. Is this evidence that the mean nicotine content is actually higher than advertised? To answer this, test the hypotheses $H_0: \mu = 1.5, H_a: \mu > 1.5$ at the 5% significance level. You conclude (A) That $ H_0 $ should be rejected. (B) That $ H_0 $ should not be rejected. (C) That $ H_{a} $ should be rejected. (D) There is a $ 5\% $ chance that the null hypothesis is true. (E) There is a $ 5\% $ chance that the alternative hypothesis is true.

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