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'.

Problem: the product of a and b is equal to 12 more than twice the sum of a and b . if b = 10 , what is the value of b - a ? 
Options: a ) 2 , b ) 5 , c ) 7 , d ) 6 , e ) 35
d

Problem: a company produces on an average 4000 items per month for the first 3 months . how many items it must produce on an average per month over the next 9 months , to average of 4375 items per month over the whole ? 
Options: a ) 4500 , b ) 4600 , c ) 4680 , d ) 4710 , e ) none
a

Problem: ( 128.5 x 60 ) + ( 13.8 x 65 ) = ? x 25 
Options: a ) 524.48 , b ) 344.28 , c ) 574.36 , d ) 585.64 , e ) 595.46

b