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: when the perimeter of a regular polygon is divided by 5 , the length of a side is 25 . what is the name of the polygon ? what is the perimeter ? 
Options: ['a ) 125', 'b ) 126', 'c ) 127', 'd ) 128', 'e ) 129']

Answer: a


Question: Problem: the speed of a boat in still water is 15 km / hr and the rate of the current is 3 km / hr . the distance travelled downstream in 12 minutes is 
Options: a ) 1.2 km , b ) 1.8 km , c ) 2.4 km , d ) 3.6 km , e ) none

Answer: d


Question: Problem: an empty tank be filled with an inlet pipe ‘ a ’ in 42 minutes . after 12 minutes an outlet pipe ‘ b ’ is opened which can empty the tank in 30 minutes . after 6 minutes another inlet pipe ‘ c ’ opened into the same tank , which can fill the tank in 35 minutes and the tank is filled . find the time taken to fill the tank ? 
Options: a ) 51.6 , b ) 51.5 , c ) 51.7 , d ) 51.1 , e ) 51.0

Answer:
b