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: a train 140 meters long takes 6 seconds to cross a man walking at 5 kmph in the direction opposite to that of the train . find the speed of the train . 
Options: a ) 45 kmph , b ) 50 kmph , c ) 55 kmph , d ) 60 kmph , e ) 79 kmph

A: e
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Q: Problem: the radius of a semi circle is 70 cm then its perimeter is ? 
Options: a ) 32.8 , b ) 32.4 , c ) 360 , d ) 32.2 , e ) 32.9

A: c
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Q: Problem: calculate the number of bricks , each measuring 25 cm x 15 cm x 8 cm required to construct a wall of dimensions 10 m x 4 m x 5 m when 10 % of its volume is occupied by concrete ? 
Options: a ) 6000 , b ) 5400 , c ) 3800 , d ) 4700 , e ) 2500

A:
a
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