6.7. According to a union agreement, the mean income for all senior-level assembly-line workers in a large company equals $500 per week. A representative of a women's group decides to analyze whether the mean income /x for female employees matches this norm. For a random sample of nine female employees, y = $410 and s = $90.

(a) Test whether the mean income of female employees differsfrom $500 perweek. Include assumptions, hypotheses, test statistic, and Pvalue. Interpret the result.

(b) Report the P-value for Hu: /r < 500. Interpret.

(c) Report and interpret the P-value for Ha:

ix > 500. {Hint: The P-values for the two possible one-sided tests must sum to 1.)