mean_age = survey_data.Age.dropna().mean()
max_age = survey_data.Age.dropna().max()
min_age = survey_data.Age.dropna().min()
dataframe['Age'] = dataframe['Age'].apply(lambda x: (x - mean_age) / (
    max_age - min_age))
How can I normalize the data in a range of columns in my pandas dataframe