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'.

[EX Q]: Problem: if one root of the equation 2 x ^ 2 + 3 x – k = 0 is 5 , what is the value of k ? 
Options: a ) 65 , b ) 79 , c ) 68 , d ) 87 , e ) 90
[EX A]: a

[EX Q]: Problem: a certain social security recipient will receive an annual benefit of $ 12,000 provided he has annual earnings of $ 9,360 or less , but the benefit will be reduced by $ 1 for every $ 3 of annual earnings over $ 9,360 . what amount of total annual earnings would result in a 40 percent reduction in the recipient ' s annual social security benefit ? ( assume social security benefits are not counted as part of annual earnings . ) 
Options: a ) $ 15,360 , b ) $ 17,360 , c ) $ 18,000 , d ) $ 21,360 , e ) $ 30,960
[EX A]: e

[EX Q]: Problem: the sum of the even numbers between 1 and n is 85 * 86 , where n is an odd number , then n = ? 
Options: a ) 163 , b ) 171 , c ) 179 , d ) 185 , e ) 191
[EX A]:
b