CREATE TABLE Student (StuID INT, LName VARCHAR, Fname VARCHAR, Age INT, Sex VARCHAR, Major INT, Advisor INT, city_code VARCHAR)
CREATE TABLE Has_Allergy (StuID INT, Allergy VARCHAR)
CREATE TABLE Allergy_Type (Allergy VARCHAR, AllergyType VARCHAR)

Show the average age for male and female students with a bar chart, rank by the mean age in descending.
SELECT Sex, AVG(Age) FROM Student GROUP BY Sex ORDER BY AVG(Age) DESC
SELECT "Sex", AVG("Age") FROM "Student" GROUP BY "Sex" ORDER BY AVG("Age") DESC NULLS LAST