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: raja complete a journey in 10 hours . he travels first half of the journey at the rate of 21 km / hr and second half at the rate of 24 km / hr . find the total journey in km . 
Options: a ) 200 km , b ) 250 km , c ) 224 km , d ) 255 km , e ) 260 km

A: c
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Q: Problem: the radius of a circular wheel is 1.75 m , how many revolutions will it make in traveling 1 km ? 
Options: ['a ) 1000', 'b ) 2788', 'c ) 2677', 'd ) 2899', 'e ) 2771']

A: a
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Q: Problem: in a covering a certain distance , the speeds of a and b are in the ratio of 3 : 4 . a takes 30 minutes more than b to reach the destination . the time taken by a to reach the destination is ? 
Options: a ) 8 hrs , b ) 9 hrs , c ) 2 hrs , d ) 2 hrs , e ) 9 hrs

A:
c
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