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: if the diameter of circle r is 20 % of the diameter of circle s , the area of circle r is what percent of the area of circle s ? 
Options: a ) 5 % , b ) 10 % , c ) 15 % , d ) 14 % , e ) 4 %

A: e
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Q: Problem: if the area of a square with sides of length 5 centimeters is equal to the area of a rectangle with a width of 4 centimeters , what is the length of the rectangle , in centimeters ? 
Options: a ) 4 , b ) 8 , c ) 12 , d ) 7 , e ) 18

A: d
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Q: Problem: the circumference of a circle is equal to 72 pi . find the radius of this circle . 
Options: ['a ) 35', 'b ) 36', 'c ) 37', 'd ) 38', 'e ) 39']

A:
b
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