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: a rectangular window is twice as long as it is wide . if its perimeter is 18 feet , then what are its dimensions in feet ? 
Options: ['a ) 3 / 2 by 7 / 2', 'b ) 5 / 3 by 10 / 3', 'c ) 2 by 4', 'd ) 3 by 6', 'e ) 10 / 3 by 20 / 3']

A: d
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Q: Problem: the parameter of a square is equal to the perimeter of a rectangle of length 9 cm and breadth 6 cm . find the circumference of a semicircle whose diameter is equal to the side of the square . ( round off your answer to two decimal places ) ? 
Options: a ) 11.72 , b ) 11.52 , c ) 11.97 , d ) 10.91 , e ) 11.79

A: e
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Q: Problem: if d is the smallest positive integer such that 3,150 multiplied by d is the square of an integer , then d must be 
Options: ['a ) 2', 'b ) 5', 'c ) 6', 'd ) 7', 'e ) 14']

A:
e
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