7.20. Table 7.14 summarizes the number of hours spent in housework per week by gender, based on the 2002 GSS (variable RHHWORK).

(a) Estimate the difference between the population means for women and men.

(b) Show that the estimated standard error of the sample difference is 0.81. Interpret.

(c) Show that a 99% confidence interval for the difference is (2.3, 6.5). Interpret.

TABLE 7.14 Housework Hours Standard Gender Sample Size Mean Deviation Men 292 8.4 9.5 Women 391 12.8 11.6