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 area of a triangle is with base 10 m and height 10 m ? 
Options: a ) 11 , b ) 10 , c ) 50 , d ) 122 , e ) 12

A: c
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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: if a square mirror has a 20 - inch diagonal , what is the approximate perimeter w of the mirror , in inches ? 
Options: a ) 40 , b ) 60 , c ) 80 , d ) 100 , e ) 120

A:
b
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