In what time will a railway train 60 m long moving at the rate of 72 kmph pass a telegraph post on its way?  Select:
A) 8 sec B) 3 sec C) 2 sec D) 6 sec E) 9 sec

Rationale: "t = 60 / 72 * 18 / 5 = 3 sec answer : b"
Answer: B