Question: Self-Reported and Measured Male Heights. As a part of the National Health and Nutrition Examination Survey conducted by the Department of Health and Human Services, self-reported heights and measured heights were obtained for males aged 12-16. Listed below are sample results.

Reported height 68 71 63 70 71 60 65 64 54 63 66 72

Measured height 67.9 69.9 64.9 68.3 70.3 60.6 64.5 67.0 55.6 74.2 65.0 70.8

a. Is there sufficient evidence to support the claim that there is a difference between self-reported heights and measured heights of males aged 13-16? Uses a 0.05 significance level.

b. Construct a 95% confidence interval estimate of the mean difference between reported heights and measured heights. Interpret the resulting confidence interval, and comment on the implications of whether the confidence interval limits contain 0.