What are the districts out there?
select district_name from district
What is the name of the headquartered city of each district?
select district_name, headquartered_city from district
Which of these given districts have a city population larger than 100000?
select district_name from district where city_population > 100000
Also show the districts that have a city area greater than 10.
select district_name from district where city_area > 10 or city_population > 100000