A college professor claims that the entering class this year appears to be smarter than entering classes from previous years. He tests a random sample of 17 of this year's entering students and finds that their mean IQ score is 117, with a standard deviation of 18. The college records indicate

that the mean IQ score for entering students from previous years is 109.

a. If we assume that the IQ scores of this year's entering class are normally distributed, is there enough evidence to conclude, at the 0.01 level of significance, that the mean IQ score, , of this year's class is greater than that of previous years? State both the null and alternate hypotheses. Solve the problem with the P-value approach using the table of statistical values.

b. Construct a 98% confidence interval for the mean IQ score of the entering class this year and interpret it.