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 ratio of the radius of two circles is 1 : 3 , and then the ratio of their areas is ? 
Options: a ) 1 : 5 , b ) 1 : 6 , c ) 1 : 9 , d ) 1 : 3 , e ) 1 : 2

A: c
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Q: Problem: the slant height of a cone is 12 cm and radius of the base is 4 cm , find the curved surface of the cone . 
Options: a ) 33 , b ) 88 , c ) 48 , d ) 77 , e ) 27

A: c
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Q: Problem: it has been raining at the rate of 5 centimeters per hour . if the rain filled a cylindrical drum with a depth of 15 centimeters , and area 300 square centimeters , how long did it take to fill the drum completely ? 
Options: ['a ) 3 hours', 'b ) 4 hours 15 minutes', 'c ) 6 hours', 'd ) 2 hours 5 minutes', 'e ) 8 hours']

A:
a
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