郭敦顒回答:Answer——(a) The market demand of the weighted average price and average demandInstance data,Σ(Pi Qdi)/ΣQdi =717.5/315=2.28,i=1,2,3,4,5,6,7(b) (ii) $1.50 per kilo(c) P=2.28,Qd=45;P′=1.50,ΔP=P′-P=1.5-2.28=-0.78ΔQd=Qd×|-0.78|/2.28=45×34.2%=15.4Qd′=Qd+ΔQd=45+15,4=60.4ΣQd′=7×60.4=422(i) Give the new su...