below is question with its answer, plz explain to me in details how we arrived to this answer?

i know that they used tribgle area rule, but how we chose those exact numbers?

12. (3 points) Calculate the (i) consumer surplus, (ii) producer surplus, and (iii) deadweight loss if Q = 2 units of the good are produced and the market price is P = 2? (i) cs = 5.5*(4)*2 1 (4:2)*2 = 6 (ii) PS = 0.5*(1-0)*2 + (2-1)*2 = 3 (iii) DWL = 0.5*(4-2)*(41) = 3