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: 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
c

Problem: a lady builds 8 cm length , 15 cm width , and 5 cm height box using 10 cubic cm cubes . what is the minimum number of cubes required to build the box ? 
Options: a ) 107 , b ) 60 , c ) 70 , d ) 89 , e ) 78
b

Problem: the cube root of . 000343 is 
Options: a ) 0.7 , b ) 0.07 , c ) 0.007 , d ) 7 , e ) none of these

b