Two trains, A and B, are 200 meters and 310 meters long respectively. They are running on parallel tracks in opposite directions with speeds of 72 km/hr and 36 km/hr. In exactly how many seconds will they completely cross each other?

Two trains, A and B, are 200 meters and 150 meters long respectively. They are running on parallel tracks in opposite directions with speeds of 72 km/hr and 54 km/hr. In exactly how many seconds will they completely cross each other?

Two trains, A and B, are 200 meters and 310 meters long respectively. They are running on parallel tracks in opposite directions with speeds of 36 km/hr and 18 km/hr. In exactly how many seconds will they completely cross each other?

Two trains, A and B, are 150 meters and 170 meters long respectively. They are running on parallel tracks in opposite directions with speeds of 90 km/hr and 54 km/hr. In exactly how many seconds will they completely cross each other?

Two trains, A and B, are 100 meters and 200 meters long respectively. They are running on parallel tracks in opposite directions with speeds of 54 km/hr and 54 km/hr. In exactly how many seconds will they completely cross each other?

Two trains, A and B, are 100 meters and 170 meters long respectively. They are running on parallel tracks in opposite directions with speeds of 90 km/hr and 18 km/hr. In exactly how many seconds will they completely cross each other?

Two trains, A and B, are 200 meters and 200 meters long respectively. They are running on parallel tracks in opposite directions with speeds of 36 km/hr and 54 km/hr. In exactly how many seconds will they completely cross each other?