Consumer and Producer Surplus

(10 - 6) * 12 / 2 = 24

(10 - 5) * 15 / 2 = 37.5

37.5 - 24 = 13.5 

(10 - 6) * 14 / 2 = 28

(6 - 3) * 14 / 2 = 21

(10 - 3) * 14 / 2 = 49

(4 - 2) * 3 / 2 = 14