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: the slant height of a cone is 22 cm and radius of the base is 7 cm , find the curved surface of the cone ?
Options: a ) 426 , b ) 284 , c ) 483 , d ) 256 , e ) 428
[A]: c

[Q]: Problem: 30 square stone slabs of equal size were needed to cover a floor area of 50.7 sq . m . find the length of each stone slab ?
Options: a ) 130 cm , b ) 767 cm , c ) 88 cm , d ) 666 cm , e ) 776 cm
[A]: a

[Q]: Problem: the product of the squares of two positive integers is 81 . how many pairs of positive integers satisfy this condition ?
Options: a ) 0 , b ) 1 , c ) 2 , d ) 3 , e ) 4
[A]:
c