To what extent does a patient's body mass index (bmi) predict the medical insurance charges for their care? The file insurance.csv Download insurance.csv contains data on 325 patients from the southwest region who incurred medical insurance charges, including the following variables: age: age of patient in years sex: gender of patient bmi: body mass index of patient children: the number of children the patient has smoker: whether or not the patient is a smoker region: region in which patient resides charges: insurance charges for patient's medical care in dollars Fit a linear model for charges in terms of bmi. Based on these model results, what is the proportion of variability in charges explained by the regression on bmi? Round your answer to 2 decimal places