F.4 Econ.......

a) 政府提供的居屋住宅單位數目不足以應付申請‧ that is, excess demand below equilibrium price. Thus, you need to draw a downwards-sloping demand curve and upwards sloping supply curve, with selling price below equilibrium price hence resulting in excess demand.
b) As the upper limit on family income lowers, the demand would be increased, thus shifting the demand curve to the right. Using the same graphs, the excess demand would become larger at the same selling price, even though the equilibrium price should be higher.

2008-01-02 11:42:06 補充：
b) The number of families qualified to apply 居屋 would decrease, hence, demand curve will shift to left. The equilibrium price will go lower hence excess demand will be reduced.

a:
The reporter said that there is NOT ENOUGH housing unit under HOS, that means, there is EXCESS DEMAND(shortage) and the market price is under equilibrium price.
先畫P & Q axis ,打個叉(supply curve係直線!!!!),畫條橫線係個叉下面, quantity transacted 就係橫線同demand curve 對下個點

b:income restriction from $ 21000 lower to $18000,that means
如果一個人每個月收$19000, 下調後佢就無樓買!!!
therefore, demand DECREASES, demand curve shift to the LEFT, SHORTAGE will DECREASE, or even DISAPPEAR!!!!
DEMAND CURVE 向左"吞",畫好後Quantity transacted 會少左!!!
remark: price 已set 定, no need to change.