1. FEV (forced expiratory volume) is an index of pulmonary function that measures the volume of air expelled after one second of constant effort. The data fev.csv contains determinations of FEV on 654 children ages 3-19 who were seen in the Childhood Respiratory Disease Study in East Boston, Massachusetts. The variables in the data include:

ID: subject ID number

Age: age in years

FEV: FEV in liters

Height: height in inches

Sex: Male or Female

Smoker: non = nonsmoker, Current = current smoker

1. Make a boxplot of the FEV for children with age 3-8 years, 9-12 years, and 13 years or above. Does it appear that the FEV is the same for children from these three age groups?