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'.

Problem: a car travels uphill at 30 km / hr and downhill at 90 km / hr . it goes 100 km uphill and 50 km downhill . find the average speed of the car ? 
Options: a ) 32 kmph , b ) 39 kmph , c ) 34 kmph , d ) 35 kmph , e ) 36 kmph
b

Problem: if a ( a - 2 ) = 2 and b ( b - 2 ) = 2 , where a ≠ b , then a + b = 
Options: a ) − 1 , b ) − 2 , c ) 4 , d ) 46 , e ) 48
a

Problem: in a room with 10 people , 7 people have exactly 1 friend in the room and 6 people have exactly 2 friends in the room ( assuming that friendship is a mutual relationship , i . e . if jane is paul ' s friend , paul is jane ' s friend ) . if two individuals are selected from the room at random , what is the probability that those two individuals are not friends ? 
Options: a ) 5 / 21 , b ) 3 / 7 , c ) 4 / 7 , d ) 5 / 7 , e ) 49 / 45

e