Task: Question Answering
Input (English): Problem: if a and b are the two values of t that satisfy the equation t ^ 2 â € “ 12 t + 20 = 0 , with a > b , what is the value of a â € “ b ? 
Options: a ) 2 , b ) 4 , c ) 6 , d ) 8 , e ) 10
Output (English): d