In what time will two trains cross each other completely, which are running on the same parallel lines in opposite directions, each 100 m in length both trains running with a speed of 80 kmph?
Choose one:	A) 4.5 sec	B) 4.8 sec	C) 4.2 sec	D) 5.0 sec	E) 5.2 sec

Rationale: d = 100 m + 100 m = 200 m * 1 / 1000 = 0.2 kms rs = 80 + 80 = 160 kmph t = ( 0.2 / 160 ) * 3600 = 4.5 sec answer : a
Answer: A