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'.

[Q]: Problem: if z is not equal to zero , and z = 6 zs − 9 s 2 − − − − − − − − √ z = 6 zs − 9 s 2 , then z equals : 
Options: a ) s , b ) 3 s , c ) 4 s , d ) - 3 s , e ) - 4 s
[A]: b


[Q]: Problem: a store reported total sales of $ 460 million for february of this year . if the total sales for the same month last year was $ 320 million , approximately what was the percent increase in sales ? 
Options: a ) 2 % , b ) 17 % , c ) 44 % , d ) 65 % , e ) 83 %
[A]: c


[Q]: Problem: if a : b = 4 : 1 , then find ( a - 3 b ) / ( 2 a - b ) ? 
Options: a ) 6 / 7 , b ) 1 / 7 , c ) 5 / 7 , d ) 3 / 2 , e ) 4 / 7
[A]:
b