what is the icao code for American Airlines?
select icao from airlines where name = 'American Airlines'
which routes are operated by American Airlines?
select * from airlines as t1 join routes as t2 on t1.alid = t2.alid where t1.name = 'American Airlines'
please count the number of routes.
select count(*) from airlines as t1 join routes as t2 on t1.alid = t2.alid where t1.name = 'American Airlines'