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 a : b = 2 : 3 , b : c = 4 : 5 and c : d = 5 : 9 then a : d is equal to : 
Options: a ) 11 : 17 , b ) 8 : 27 , c ) 5 : 9 , d ) 2 : 9 , e ) none
[A]: b


[Q]: Problem: how many even 4 - digit numbers can be formed , so that the numbers are divisible by 4 and no two digits are repeated ? 
Options: a ) 336 , b ) 784 , c ) 1120 , d ) 1804 , e ) 1936
[A]: c


[Q]: Problem: given that x and y are events such that z ( x ) = 0.02 z ( y ) = 0.10 z ( xny ) = 0.10 z ( x | y ) = find z ( x | y ) and z ( x | y ) 
Options: a ) 1 / 5 , b ) 1 / 6 , c ) 1 / 6 , d ) 1 / 4 , e ) 1 / 2
[A]:
a