In this task, you need to answer the given multiple-choice question on geometry. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: the least perfect square , which is divisible by each of 21 , 36 and 66 is 
Options: a ) 213414 , b ) 213424 , c ) 213434 , d ) 213444 , e ) none of these

A: d
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Q: Problem: the area of a parallelogram is 72 sq m and its altitude is twice the corresponding base . then the length of the base is ? 
Options: a ) 6 , b ) 16 , c ) 8 , d ) 36 , e ) none

A: a
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Q: Problem: 5 cylinders are built successively , the first is 4 meters tall and the following cylinders are each 4 meters taller than the previous . if the perimeter is 10 pi m , what is the total surface area of the 5 cylinders , excluding the bases of each cylinder ? 
Options: ['a ) 725 pi sq m', 'b ) 1025 pi sq m', 'c ) 600 pi sq m', 'd ) 125 pi sq m', 'e ) 850 pi sq m']

A:
a
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