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 a and b are 125 m and 150 m long and are moving at one another at 54 km / hr and 36 km / hr respectively . arun is sitting on coach b 1 of train a . calculate the time taken by arun to completely cross train b . 
Options: a ) 10 s , b ) 11 s , c ) 4 s , d ) 8 s , e ) 12 s
[EX A]: b

[EX Q]: Problem: today mary ’ s father is 4 times as old as mary . 3 years ago , he was 5 times as old . how old is mary today ? 
Options: a ) 6 , b ) 8 , c ) 10 , d ) 12 , e ) 14
[EX A]: d

[EX Q]: Problem: a car started running at a speed of 30 km / hr and the speed of the car was increased by 2 km / hr at the end of every hour . find the total distance covered by the car in the first 12 hours of the journey . 
Options: a ) 342 km , b ) 352 km , c ) 642 km , d ) 742 km , e ) 492 km
[EX A]:
e