A train is 310 meter long is running at a speed of 45 km/hour. In what time will it pass a bridge of 140 meter length?	Select the correct option:
A) 36 seconds  B) 18 seconds  C) 40 seconds  D) 19 seconds  E) 45 seconds

Rationale: "speed = 45 km / hr = 45 * ( 5 / 18 ) m / sec = 25 / 2 m / sec total distance = 310 + 140 = 500 meter time = distance / speed = 450 * ( 2 / 25 ) = 36 seconds answer : a"
Answer: A