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 start walking from a place at a uniform speed of 4 kmph in a particular direction . after half an hour , b starts from the same place and walks in the same direction as a at a uniform speed and overtakes a after 1 hour 48 minutes . find the speed of b . 
Options: a ) 4.7 kmph , b ) 4.6 kmph , c ) 4 kmph , d ) 7 kmph , e ) 5.3 kmph

A: b
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Q: Problem: ajay can ride 50 km in 1 hour . in how many hours he can ride 1250 km ? 
Options: a ) 10 hrs , b ) 15 hrs , c ) 20 hrs , d ) 25 hrs , e ) 18 hrs

A: d
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Q: Problem: mars travels around the sun at a speed of approximately 15 miles per second . the approximate speed is how many miles per hour ? 
Options: a ) 48,000 , b ) 51,000 , c ) 54,000 , d ) 57,000 , e ) 60,000

A:
c
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