The mean + 1 sd of In [calcium intake (mg)] among 25
females, 12 to 14 years of age, below the poverty level is
$6.56+0.64.$

Similarly, the mean + 1 sd of In [calcium intake (mg)] among 40 females, 12 to 14 years of age, above the poverty level is$6.80+0.76.$

8.2 Test for a significant difference between the variances of the two groups.

8.3 What is the appropriate procedure to test for a signifi- cant difference in means between the two groups?

8.4 Implement the procedure in Problem 8.3 using the critical-value method.

8.5 What is the p-value corresponding to your answer to Problem 8.4?

8.6 Compute a$95\mathrm{\%}$ Cl for the difference in means
between the two groups.

Similarly, the mean + 1 sd of In [calcium intake (mg)] among 40 females, 12 to 14 years of age, above the poverty level is

8.2 Test for a significant difference between the variances of the two groups.

8.3 What is the appropriate procedure to test for a signifi- cant difference in means between the two groups?

8.4 Implement the procedure in Problem 8.3 using the critical-value method.

8.5 What is the p-value corresponding to your answer to Problem 8.4?

8.6 Compute a