"Demand" and "quantity demanded" are two different concepts in Economi cs.

需求和需求量是经济学中两个不同的概念。

The total annual quantity demanded in such market is estimated to be about 50000 sets.

这样的市场每年需求总量估计大约是50000套。

That means there is a large amount of quantity demanded and a big market of tea in Shantou.

这意味着在汕头，茶叶巨大的需求量带来了巨大的市场。

Income elasticity measures the responsiveness of changes in quantity demanded to changes in income.

收进弹性办法在收进的改变需求数目改变的响应能力。

Similarly, when the price is below p*, the quantity supplied qsis less than the quantity demanded qd.

同样的，当价格低于 p*时，供给数量qs 小于需求数量qd 。 这将导致部分顾客买不到商品，将出现买家高价求购，卖家哄抬价格的局面。