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 radius of the base of cone is 3 cm and height is 4 cm . find the volume of the cone ? 
Options: ['a ) 12', 'b ) 75', 'c ) 97', 'd ) 15', 'e ) 91']

A: a
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Q: Problem: the radius of a sphere is increased by 50 % . the increase in surface area of the sphere is : 
Options: a ) 168 , b ) 125 , c ) 186 , d ) 197 , e ) 191

A: b
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Q: Problem: the diagonal of a rhombus are 65 m and 60 m . its area is : 
Options: a ) 1940 , b ) 1950 , c ) 1960 , d ) 1990 , e ) 1980

A:
b
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