In this task, you need to answer the given multiple-choice question on geometry. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
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Question: Problem: a cylindrical bucket of height 36 cm and radius 21 cm is filled with sand . the bucket is emptied on the ground and a conical heap of sand is formed , the height of the heap being 12 cm . the radius of the heap at the base is : 
Options: ['a ) 63 cm', 'b ) 53 cm', 'c ) 56 cm', 'd ) 66 cm', 'e ) none of these']

Answer: a


Question: Problem: the area of a square field is 1600 km 2 . how long will it take for a horse to run around at the speed of 16 km / h ? 
Options: a ) 12 h , b ) 10 h , c ) 8 h , d ) 6 h , e ) none of these

Answer: b


Question: Problem: the side of a square has the length of 6 . what is the area of the region shaded ? 
Options: ['a ) 48 - 8 π', 'b ) 48 - 6 π', 'c ) 24 + 6 π', 'd ) 16 + 8 π', 'e ) 64 - 8 π']

Answer:
b