In this task, you need to answer the given multiple-choice question on geometry. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Problem: find the area of a parallelogram with base 18 cm and height 10 cm ? 
Options: a ) 281 , b ) 284 , c ) 288 , d ) 255 , e ) 180
e

Problem: if the height of a cone is increased by 140 % then its volume is increased by ? 
Options: ['a ) 100', 'b ) 140', 'c ) 998', 'd ) 729', 'e ) 2879']
b

Problem: how many internal diagonals does a nonagon ( nine sided polygon ) have ? 
Options: a ) 25 , b ) 27 , c ) 40 , d ) 56 , e ) 80

b