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 slant height of a cone is 13 cm and radius of the base is 9 cm , find the curved surface of the cone ? 
Options: a ) 367 , b ) 378 , c ) 365 , d ) 26 , e ) 28

A: a
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Q: Problem: find the smallest number that should be multiplied with 54000 to make it a perfect cube . 
Options: ['a ) 4', 'b ) 5', 'c ) 6', 'd ) 3', 'e ) 7']

A: a
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Q: Problem: a rectangle having length 120 cm and width 50 cm . if the length of the rectangle is increased by ten percent then how much percent the breadth should be decreased so as to maintain the same area . 
Options: a ) 25 % , b ) 33.33 % , c ) 40 % , d ) 7.69 % , e ) none of these

A:
d
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