Q1) As part of contract negotiations, management claims that mean annual salary for clerical workers is $30,000.  Union would like to illustrate the mean is lower.  Random sample of 17 annual clerical salaries is collected and results sample mean of $28,157 and standard deviation of $3500.  Is this enough evidence to support Union's position?  Use significance level of a = 0.05.  You may suppose the mean annual salaries are normally distributed.

Q2) It is usually accepted that convicted burglars spend average of 18.7 months in jail.  To check this claim researcher takes random sample of 50 such cases from court files and determines that x-bar = 20.5 months.  Supposing σ is known to be 7.9 months; does sample evidence support belief that average stay is 18.7 months at the 0.025 level of significance?