A bus takes 2 hours to reach from station A to station B and then 3hours to return from station B to station A. Find the average velocity of the bus.

The freezing and boiling point of a substance changes as the air pressure around it changes. for example, at a lower air pressure (higher altitude) it is easier for water molecules to escape from liquid into the air. in a high altitude city such as denver, colorado compared to a sea-level city such as houston, texas, water