A train 300 m long is running at a speed of 78 km/hr. If it crosses a tunnel in 1 min, then the length of the tunnel is?	Choose the correct choice from the following answers:
A) 298 m
B) 268 m
C) 500 m
D) 267 m
E) 1000 m
Speed = 78 * 5/18 = 65/3 m/sec.   Time = 1 min = 60 sec.   Let the length of the train be x meters.   Then, (300 + x)/60 = 65/3   x = 1000 m.   Answer: 1000 m
<result>E</result>
A train 300 m long is running at a speed of 78 km/hr. If it crosses a tunnel in 1 min, then the length of the tunnel is?