Here group 1,with demand curve D,is charged Pp and group 2, with the more elastic demand curve D2,is charged the lower price P2. Marginal cost depends on the total quantity produced Q Note that Q and Q2 are chosen so that MR1=MR2=MC.Here group 1, with demand curve D1 , is charged Pl , and group 2, with the more elastic demand curve D2 , is charged the lower price P2 . Marginal cost depends on the total quantity produced QT. Note that Q1 and Q2 are chosen so that MR1 = MR2 = MC