Correct Answer :
D. 245 meters
Let the length of bridge is X
Speed of train is = 45*(5/18) m/sec = 25/2 m/sec
Time = 30 seconds
Total distance = 130+x
We know Speed = distance/time
so,130+x30=252⇒2(130+x)=750x=245 metersSo length of the bridge is 245 meters