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 of equal lengths take 10 sec and 8 sec respectively to cross a telegraph post . if the length of each train be 120 m , in what time will they cross other travelling in opposite direction ? 
Options: a ) 22 , b ) 12 , c ) 9 , d ) 99 , e ) 21
[EX A]: c

[EX Q]: Problem: a , b and c can complete a piece of work in 24 , 6 and 12 days respectively . working together , they will complete the same work in : 
Options: a ) 33 / 7 , b ) 43 / 7 , c ) 24 / 7 , d ) 19 / 7 , e ) none
[EX A]: c

[EX Q]: Problem: how many bricks each measuring 20 cm x 13.25 cm x 8 cm , will be needed to build a wall 7 m x 8 m x 15.5 m 
Options: a ) 5600 , b ) 4600 , c ) 4094 , d ) 7200 , e ) none of these
[EX A]:
c