7. A train 250 metres long, running with a speed of 50 km/hr will pass an electric pole in:

8. A train speeds past a pole in 15 seconds and speeds past a platform 100 metres long in 25 seconds. Its length in metres is:

9. A train 700 m long is running at the speed of 72 km per hour It in crosses a tunnel in 1 minute, then the length of the tunnel is: