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 spherical balls lie on the ground touching . if one of the balls has a radius of 10 cm , and the point of contact is 12 cm above the ground , what is the radius of the other ball ( in centimeters ) ?
Options: a ) 14 , b ) 15 , c ) 16 , d ) 18 , e ) 20
[EX A]: b

[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: how long does a train 120 m long running at the speed of 70 km / hr takes to cross a bridge 145 m length ?
Options: a ) 13.9 sec , b ) 12.1 sec , c ) 17.9 sec , d ) 13.9 sec , e ) 47.98 sec
[EX A]:
d