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 bicycle wheel has a diameter of 0.51 m . how many complete revolutions does it make in 1 km ? 
Options: a ) 246 , b ) 448 , c ) 1408 , d ) 710 , e ) 624

A: e
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Q: Problem: a man rows his boat 75 km downstream and 45 km upstream , taking 2 1 / 2 hours each time . find the speed of the stream ? 
Options: a ) 6 , b ) 7 , c ) 5 , d ) 8 , e ) 9

A: a
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Q: Problem: walking with 4 / 5 of my usual speed , i miss the bus by 6 minutes . what is my usual time ? 
Options: a ) 16 min , b ) 26 min , c ) 34 min , d ) 24 min , e ) 12 min

A:
d
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