5.  Given below are the birth weights of babies born to mothers who took special vitamin supplements while pregnant:   3.13…

5.  Given below are the birth weights of babies born to mothers who took special vitamin supplements while pregnant:  

3.13    4.57    3.93    4.33    3.39    3.68    4.68    3.52

3.02    4.29    2.47    4.13    4.47    3.22    3.43    2.54

a.  Make a 99% confidence interval for the mean weight of babies whose mothers take vitamin supplements.

b.  Do a hypothesis test to determine if these babies weight is more than the mean weight for the population of all babies which is 3.39 kg using α = .005

c.  In a short paragraph, describe the relationship between your answer to part (a) and your answer to part (b).

6. A student wanted to study the ages of couples applying for marriage licenses in his county.  He studied a sample of 94 marriage licenses and found that in 67 cases the husband was older than the wife. Do the sample data provide evidence that the husband is usually older than the wife among couples applying for marriage licenses in that county? Explain briefly and justify your answer using the methods studied in this course.  Use α= 0.05 as the level of significance.