The correct option is C 12 ms−1, 50 s
Length of the train, D=60 m,
Time taken to cross the pole, T=5 s,
Length of the bridge =540 m
Speed of the train, s=DT
Speed of the train, s=605=12 ms−1
Now, distance to be covered to cross a 540 m long bridge is sum of Length of the train and Length of the bridge.
Time taken=60012=50 s
∴ Speed of the train is 12 ms−1 and the time it will take to cross the bridge is 50 s.