Two trains, each of length 100 m, are running on parallel tracks. One overtakes the other in 20 seconds when they run in the same direction, and crosses the other in 10 seconds when they run in opposite directions. What are the velocities of the two trains?

Options:

• A: 20 m/s and 10 m/s
• B: 12 m/s and 8 m/s
• C: 15 m/s and 5 m/s
• D: 25 m/s and 15 m/s

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