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'.

Q: 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

A: a
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Q: Problem: 45 men working 8 hours per day dig 40 m deep . how many extra men should be put to dig to a depth of 50 m working 6 hours per day ? 
Options: a ) 10 , b ) 20 , c ) 30 , d ) 40 , e ) 50

A: c
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Q: Problem: the length of a train and that of a platform are equal . if with a speed of 216 k / hr , the train crosses the platform in one minute , then the length of the train ( in meters ) is ? 
Options: a ) 1752 , b ) 1799 , c ) 1719 , d ) 1750 , e ) 1800

A:
e
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