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: what is the measure of the radius of the circle inscribed in a triangle whose sides measure 4 , 11 and 12 units ? 
Options: ['a ) 1.6 units', 'b ) 6 units', 'c ) 3 units', 'd ) 5 units', 'e ) 12 units']

A: a
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Q: Problem: what will be the cost of building a fence around a square plot with area equal to 81 sq ft , if the price per foot of building the fence is rs . 58 ? 
Options: a ) 3944 , b ) 2287 , c ) 2977 , d ) 2088 , e ) 1298

A: d
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Q: Problem: the area of a square is equal to three times the area of a rectangle of dimensions 15 cm * 5 cm . what is the perimeter of the square ? 
Options: a ) 30 , b ) 80 , c ) 50 , d ) 60 , e ) 70

A:
d
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