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'.
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Question: Problem: calculate the speed of a boat in still water ( in km / hr ) if in one hour , the boat goes 10 km / hr downstream and 4 km / hr upstream . 
Options: a ) 7 kmph , b ) 8 kmph , c ) 9 kmph , d ) 7 kmph , e ) 6 kmph

Answer: a


Question: Problem: a student travels from his house to school at 10 km / hr and reaches school 1 hour late . the next day he travels 12 km / hr and reaches school 1 hour early . what is the distance between his house and the school ? 
Options: a ) 100 , b ) 105 , c ) 110 , d ) 115 , e ) 120

Answer: e


Question: Problem: if 11.25 m of a uniform steel rod weighs 42.75 kg . what will be the weight of 10 m of the same rod ? 
Options: a ) 38 kg , b ) 25.6 kg , c ) 28 kg , d ) 26.5 kg , e ) none of these

Answer:
a