Find the cities which have exactly two airports
select city from airports group by city having count ( * ) = 2
what is the name of airport in the country Papua New Guinea
select name from airports where country = 'Papua new Guinea'
what is the elevation of Madang Airport?
select elevation from airports where name = 'Madang Airport'
What is the elevation of Goroka Airport
select elevation from airports where name = 'Goroka Airport'