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: the ratio between the speeds of two trains is 7 : 8 . if the second train runs 400 km in 4 hours , what is the the speed of the first train ? 
Options: a ) 87.0 , b ) 87.5 , c ) 87.2 , d ) 87.1 , e ) 87.4

A: b
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Q: Problem: excluding stoppages , the speed of a bus is 58 kmph and including stoppages , it is 40 kmph . for how many minutes does the bus stop per hour ? 
Options: a ) 19 , b ) 19.13 , c ) 10.5 , d ) 11.35 , e ) none of these

A: a
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Q: Problem: the speed of a boat in still water is 50 kmph and the speed of the current is 20 kmph . find the speed and upstream ? 
Options: a ) 30 kmph , b ) 40 kmph , c ) 78 kmph , d ) 15 kmph , e ) 23 kmph

A:
a
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