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 field is to be fenced on three sides leaving a side of 20 feet uncovered . if the area of the field is 256 sq . feet , how many feet of fencing will be required ? 
Options: a ) 45.6 , b ) 40 , c ) 68 , d ) 88 , e ) 92

A: a
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Q: Problem: a box measuring 49 inches long by 21 inches wide by 14 inches deep is to be filled entirely with identical cubes . no space is to be left unfilled . what is the smallest number of cubes that can accomplish this objective ? 
Options: a ) 17 , b ) 42 , c ) 54 , d ) 108 , e ) 864

A: b
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Q: Problem: the area of an isosceles trapezoid with sides of length 5 and bases of length 8 and 14 is ? 
Options: a ) 22 , b ) 32 , c ) 44 , d ) 55 , e ) 56

A:
c
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