CREATE TABLE Student (StuID INT, LName VARCHAR, Fname VARCHAR, Age INT, Sex VARCHAR, Major INT, Advisor INT, city_code VARCHAR)
CREATE TABLE Lives_in (stuid INT, dormid INT, room_number INT)
CREATE TABLE Dorm_amenity (amenid INT, amenity_name VARCHAR)
CREATE TABLE Has_amenity (dormid INT, amenid INT)
CREATE TABLE Dorm (dormid INT, dorm_name VARCHAR, student_capacity INT, gender VARCHAR)

What is the average age for each city and what are those cities Show bar chart, and list names in descending order.
SELECT city_code, AVG(Age) FROM Student GROUP BY city_code ORDER BY city_code DESC
SELECT "city_code", AVG("Age") FROM "Student" GROUP BY "city_code" ORDER BY "city_code" DESC NULLS LAST