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: the sector of a circle has radius of 21 cm and central angle 180 o . find its perimeter ?
Options: a ) 91.5 , b ) 92 , c ) 108 , d ) 94 , e ) 95

Answer: c

Question: Problem: what is the greatest possible length which can be used to measure exactly the lengths 10 m 50 cm , 14 m 55 cm and 50 cm ?
Options: a ) 20 cm , b ) 24 cm , c ) 30 cm , d ) 10 cm , e ) 5 cm

Answer: e

Question: Problem: two men are walking towards each other alongside a railway track . a freight train overtakes one of them in 20 seconds and exactly 10 minutes later meets the other man coming from the opposite direction . the train passes this man is 18 seconds . assume the velocities are constant throughout . how long after the train has passed the second man will the two men meet ?
Options: a ) 89.7 minutes , b ) 90 minutes , c ) 90.3 seconds , d ) 91 seconds , e ) none of these

Answer:
b