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 diagonals of a rhombus are 10 cm and 15 cm . find its area ? 
Options: a ) 75 , b ) 129 , c ) 150 , d ) 123 , e ) 117
[A]: a


[Q]: Problem: the mass of 1 cubic meter of a substance is 700 kilograms under certain conditions . what is the volume , in cubic centimeters , of 1 gram of this substance under these conditions ? ( 1 kilogram = 1,000 grams and 1 cubic meter = 1 , 000,000 cubic centimeters ) 
Options: a ) 0.8 , b ) 1.42 , c ) 8.0 , d ) 12.5 , e ) 80.0
[A]: b


[Q]: Problem: in a rectangular coordinate system , what is the area of a rhombus whose vertices have the coordinates ( 0 , 3.5 ) , ( 6 , 0 ) , ( 0 , - 3.5 ) , ( - 6 , 0 ) ? 
Options: a ) 42 , b ) 56 , c ) 88 , d ) 112 , e ) 116
[A]:
a