In this task, you need to answer the given multiple-choice question on geometry. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
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Question: Problem: the slant height of a cone is 13 cm and radius of the base is 9 cm , find the curved surface of the cone ?
Options: a ) 367 , b ) 378 , c ) 365 , d ) 26 , e ) 28

Answer: a

Question: Problem: the length of a rectangle is increased by 45 % and its breadth is decreased by 20 % . what is the effect on its area ?
Options: a ) 1288 , b ) 1299 , c ) 1000 , d ) 10000 , e ) 11600

Answer: e

Question: Problem: amit and ian paint a wall in alternating shifts . first amit paints alone , then ian paints alone , then amit paints alone , etc . during each of his shifts , amit paints 1 / 2 of the remaining unpainted area of the wall , while ian paints 1 / 3 of the remaining unpainted area of the wall during each of his shifts . if amit goes first , what fraction of the wall ' s area will remain unpainted after amit has completed his 6 th shift ?
Options: ['a ) 1 / 27', 'b ) 1 / 54', 'c ) 1 / 81', 'd ) 1 / 162', 'e ) 1 / 486']

Answer:
e