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'.
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Question: Problem: two trains 140 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 ( in seconds ) which they take to cross each other , is : 
Options: a ) 9 , b ) 9.6 , c ) 10 , d ) 10.8 , e ) 7

Answer: d


Question: Problem: in traveling from a dormitory to a certain city , a student went 1 / 5 of the way by foot , 2 / 3 of the way by bus , and the remaining 4 kilometers by car . what is the distance , in kilometers , from the dormitory to the city ? 
Options: a ) 30 , b ) 45 , c ) 60 , d ) 90 , e ) 120

Answer: a


Question: Problem: a cistern 10 meters long and 4 meters wide contains water up to a depth of 1 meter 25 cm . what is the total area of the wet surface ? 
Options: a ) 45 , b ) 55 , c ) 65 , d ) 75 , e ) 85

Answer:
d