Beijing Airport Shuttle Line 10: Capital Airport → South Railway Station

Hi! I want to go from Capital Airport to South Railway Station with Line 10 and have 3 questions:

- Where can I find the station of Line 10 at the airport?
- How long does it take from Capital Airport to South Railway Station with Line 10 bus?
- Can it be that the trip from Capital Airport to South Railway Station is faster with public transportation (express train and subway) because of possible heavy trafic?

Thanks!