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: if 21 lines are drawn in a plane such that no two of them are parallel and no three are concurrent , then in how many points do they intersect ? 
Options: a ) 150 , b ) 170 , c ) 190 , d ) 210 , e ) 230

Answer: d


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 man can row downstream at 16 kmph and upstream at 12 kmph . find the speed of the man in still water . 
Options: a ) 14 , b ) 13 , c ) 12 , d ) 16 , e ) 15

Answer:
a