1. A small study (n=10) is designed to assess whether there is an association between smoking in pregnancy and low birth weight. Low-birth-weight babies are those born weighing <5.5 pounds. The following data represent the birth weights, in pounds, of babies born to mothers who reported smoking in pregnancy and to those who did not.

Mother smoked during pregnancy	5.0	4.2	4.8	3.3	3.9
Mother did not smoke during pregnancy	5.1	4.9	5.3	5.4	4.6