A train running at the speed of 60 km/hr crosses a pole in 21 sec. What is the length of the train?  Choose the correct option.
A) 350 m B) 490 m C) 115 m D) 210 m E) 150 m

Rationale: "speed = 60 * 5 / 18 = 50 / 3 m / sec length of the train = speed * time = 50 / 3 * 21 = 350 m answer : a"
Answer: A