In this task, you need to answer the given multiple-choice question on geometry. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

[Q]: Problem: in a certain parallelogram the degree measure of one angle exceeds that of the other by 40 what is the degree measure of the smaller angle ? 
Options: a ) 70 , b ) 80 , c ) 85 , d ) 90 , e ) 95
[A]: a


[Q]: Problem: what is the radius of the incircle of the triangle whose sides measure 5 , 12 and 13 units ? 
Options: ['a ) 2 units', 'b ) 12 units', 'c ) 6.5 units', 'd ) 6 units', 'e ) 7.5 units']
[A]: a


[Q]: Problem: 10 business executives and 7 chairmen meet at a conference . if each business executive shakes the hand of every other business executive and every chairman once , and each chairman shakes the hand of each of the business executives but not the other chairmen , how many handshakes would take place ? 
Options: a ) 144 , b ) 131 , c ) 115 , d ) 90 , e ) 45
[A]:
c