instruction:
In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
question:
Problem: if 213 × 16 = 3408 , then 16 × 21.3 is equal to : 
Options: a ) 0.3408 , b ) 3.408 , c ) 34.08 , d ) 340.8 , e ) none of these
answer:
d


question:
Problem: if 4 xz + yw = 3 and xw + yz = 6 , what is the value of the expression ( 2 x + y ) ( 2 z + w ) ? 
Options: a ) 9 . , b ) 12 . , c ) 15 . , d ) 16 , e ) 18 .
answer:
c


question:
Problem: in the coordinate plane , points ( x , 2 ) and ( 10 , y ) are on line k . if line k passes through the origin and has slope 1 / 2 , then x + y = 
Options: a ) 4.5 , b ) 7 , c ) 9 , d ) 11 , e ) 12
answer:

c