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: 30 buckets of water fill a tank when the capacity of each bucket is 13.5 litres . how many buckets will be required to fill the same tank if the capacity of each bucket is 9 litres ? 
Options: a ) 30 , b ) 32 , c ) 45 , d ) data inadequate , e ) none of these

A: c
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Q: Problem: a , b , k start from the same place and travel in the same direction at speeds of 30 km / hr , 40 km / hr , 50 km / hr respectively . b starts two hours after a . if b and k overtake a at the same instant , how many hours after a did k start ? 
Options: a ) 2.4 , b ) 3.2 , c ) 4.0 , d ) 4.8 , e ) 5.6

A: b
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Q: Problem: excluding stoppages , the speed of a bus is 62 kmph and including stoppages , it is 56 kmph . for how many minutes does the bus stop per hour ? 
Options: a ) 70 min , b ) 16 min , c ) 7 min , d ) 6 min , e ) 40 min

A:
d
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