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: 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

Answer: a


Question: Problem: the edges of a cuboid are 4 cm , 4 cm and 6 cm . find the volume of the cuboid ? 
Options: a ) 90 , b ) 60 , c ) 96 , d ) 80 , e ) 72

Answer: c


Question: Problem: a train covers a distance of 20 km in 20 min . if it takes 9 sec to pass a telegraph post , then the length of the train is ? 
Options: a ) 150 m , b ) 200 m , c ) 120 m , d ) 225 m , e ) 160 m

Answer:
a