6. The following data is the age (in months) of when toddlers took their first step. Construct a 90% confidence interval for the true difference in mean age at first step for male and female toddlers. Female: 9 12 15 18 8 10 10 9 12 11 11 13 14 12 11 Male: 8 14 12 11 11 9 10 12 12 9 10 13 9 12 10