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 120 m and 160 m long run at the speed of 60 km / hr and 40 km / hr respectively in opposite directions on parallel tracks . the time which they take to cross each other is ? 
Options: a ) 10.9 , b ) 10.7 , c ) 10.3 , d ) 10.08 , e ) 10.2
[EX A]: d

[EX Q]: Problem: there are two tanks a & b with same capacity of 20 litres . if the water inflow rate ( speed ) in tank a is 2 litres per hour & in tank b is 4 litres per hour . how much longer tank a takes to fill than tank b ? 
Options: a ) 4 hours , b ) 5 hours , c ) 3 hours , d ) 2 hours , e ) 1 hour
[EX A]: b

[EX Q]: Problem: the spherical ball of lead 3 cm in diameter is melted and recast into 3 spherical balls . the diameters of two of these are 1 1 / 2 cm and 2 cm respectively . the diameter of third ball is ? 
Options: a ) 2.8 , b ) 2.5 , c ) 2.2 , d ) 2.0 , e ) 2.1
[EX A]:
b