A boy goes from A to B with a velocity of 20 m/min and comes back from B to A with a velocity of 30 m/min. The average velocity of the boy during the whole journey is_________
A. 24 m/min
B. 25 m/s
C. Zero
D. 20 m/min
Answer:A
A boy goes from A to B with a velocity of 20 m/min and comes back from B to A with a velocity of 30 m/min. The average velocity of the boy during the whole journey is_________
A. 24 m/min B. 25 m/s C. Zero D. 20 m/min