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'.
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Question: Problem: if a and b are the roots of the equation x 2 - 9 x + 20 = 0 , find the value of a 2 + b 2 + ab ? 
Options: a ) 57 , b ) 59 , c ) 61 , d ) 63 , e ) 65

Answer: c


Question: Problem: if xy denotes x is raised to the power y , find the last two digits of 19413843 + 19614181 
Options: a ) 67 , b ) 97 , c ) 55 , d ) 32 , e ) 62

Answer: e


Question: Problem: q is as much younger than r as he is older than t . if the sum of the ages of r and t is 50 years , what is definitely the difference between r and q ' s age ? 
Options: a ) 23 , b ) 28 , c ) 25 , d ) 19 , e ) 11

Answer:
c