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: two equal triangles constitute rhombus a . if the diagonals of rhombus are 15 cm and 20 cm long . what is the area of each triangle ? 
Options: ['a ) 300', 'b ) 150', 'c ) 75', 'd ) 40', 'e ) 20']
[A]: c


[Q]: Problem: the area of a square field is 1600 km 2 . how long will it take for a horse to run around at the speed of 16 km / h ? 
Options: a ) 12 h , b ) 10 h , c ) 8 h , d ) 6 h , e ) none of these
[A]: b


[Q]: Problem: in the rectangular coordinate system , points ( 8 , 0 ) and ( – 8 , 0 ) both lie on circle c . what is the maximum possible value of the radius of c ? 
Options: ['a ) 2', 'b ) 4', 'c ) 8', 'd ) 16', 'e ) none of the above']
[A]:
c