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 cone of height 9 cm with diameter of its base 18 cm is carved out from a wooden solid sphere of radius 9 cm . the percentage of the wood wasted is : 
Options: ['a ) 45 %', 'b ) 56 %', 'c ) 67 %', 'd ) 75 %', 'e ) none of these']

A: d
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Q: Problem: the circumferences of two circles are 268 meters and 380 meters . find the difference between the areas of the larger and the smaller circles . 
Options: a ) 388.15 , b ) 2992 , c ) 4312.5 , d ) 2887.27 , e ) 5773.09

A: e
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Q: Problem: 30 square stone slabs of equal size were needed to cover a floor area of 67.5 sq . m . find the length of each stone slab ? 
Options: a ) 150 cm , b ) 767 cm , c ) 88 cm , d ) 666 cm , e ) 776 cm

A:
a
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