In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

[EX Q]: Problem: two trains t 1 and t 2 start simultaneously from two stations x and y respectively towards each other . if they are 70 km apart both 3 and 6 hours after start , then find the distance between the two stations . 
Options: a ) 210 km , b ) 240 km , c ) 220 km , d ) 180 km , e ) 190 km
[EX A]: a

[EX Q]: Problem: if a train , travelling at a speed of 180 kmph , crosses a pole in 5 sec , then the length of train is ? 
Options: a ) 250 m , b ) 112 m , c ) 117 m , d ) 125 m , e ) 123 m
[EX A]: a

[EX Q]: Problem: a room 11 m 47 cm long and 7 m 77 cm broad is to be paved with square tiles . find the least number of square tiles required to cover the floor . 
Options: a ) 636 , b ) 640 , c ) 647 , d ) 651 , e ) 675
[EX A]:
d