Explanation:

- Trains A and B are moving in the same direction.

- Train A travels at 40 km/h.

- Train B travels faster, at 60 km/h.

- Both start from the same place at the same time.

To find:

- The distance between the two trains after 1 hour.

Calculations:

- In 1 hour, Train A covers 40 km.

- In 1 hour, Train B covers 60 km.

- The difference in distance covered by train B in 1 hour = 60 km - 40 km.

Therefore:

- The distance between the two trains after 1 hour is 20 km.

Correct Answer:

- Option: 2, 20 km.

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