2. Each student in a class of 40 play at least one indoor game, chess, word factory and scrabble. 18 play chess, 20 play word factory, 7 play chess and scrabble, 12 play scrabble and word factory and 4 play chess, word factory and scrabble. Find the number of students who play:

a. Chess only
b. Word factory only
C. Scrabble only
d. Chess and scrabble
e. All of the indoor game​