qqp question1: A train moves on rails from A to B. It goes from A to B with speed 60km/hr and returns from B to A with speed 40km/hr. What is the average velocity? question2: Mathematical Puzzles: A car covers 1/3 of the distance with a speed of 20 km/hr and 2/3 of the distance with a speed of 60 km/hr. What is the average speed?