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: 9 spheres of the same size are made from melting a solid cylinder of 16 cm diameter and 12 cm height . what is the diameter of each sphere ?
Options: ['a ) 4 cm', 'b ) 6 cm', 'c ) 8 cm', 'd ) 10 cm', 'e ) 12 cm']

Answer: c

Question: Problem: a train running at the speed of 120 km / hr crosses a pole in 18 seconds . what is the length of the train ?
Options: a ) 560 , b ) 570 , c ) 580 , d ) 590 , e ) 600

Answer: e

Question: Problem: a train passes a station platform in 50 sec and a man standing on the platform in 20 sec . if the speed of the train is 54 km / hr . what is the length of the platform ?
Options: a ) 615 m , b ) 240 m , c ) 168 m , d ) 300 m , e ) 691 m

Answer:
d