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 21 cm and radius of the base is 10 cm , find the curved surface of the cone .
Options: a ) 330 , b ) 770 , c ) 660 , d ) 100 , e ) 600

Answer: c

Question: Problem: sides of a triangle are 13 cm . 14 cm . and 15 cm . respectively . calculate the area of triangle .
Options: ['a ) 80', 'b ) 82', 'c ) 84', 'd ) 86', 'e ) 88']

Answer: c

Question: Problem: the area of an isosceles trapezoid with sides of length 5 and bases of length 11 and 17 is ?
Options: a ) 48 , b ) 52 , c ) 54 , d ) 56 , e ) 46

Answer:
d