新古典主义地租模型中的代表阿兰索的主要贡献在于：将空间作为地租的一个核心问题进行了考

短文改错（共10小题；每小题1分，满分10分）

I often quarrel about my mother over whether I can watch TV after school. She holds the view that senior students have to make a full use of every minute to work hardly at their lessons. It seems to me that once I am allowed to do that, I’ll be unable to control myself and forgot all about my study. She also thinks it is bad for my eye. But I really can accept her ideas.

In my opinion, watch TV can set my mind at rest after a day’s hard work. Beside, it is important for us to know that has happened at home and abroad. Thus, we shouldn’t be forbidden to watch TV.

关于期货市场的“投机”，以下说法不正确的是( )。

A．投机是套期保值得以实现的必要条件

B．没有投机就没有期货市场

C．投资者是价格风险的承担者

D．通过投机者的套利行为，可以实现价格均衡和防止价格的过分波动，创造一个稳定市场

某水样用的0.1000mol/LHCl溶液滴定至酚酞终点，用去18.00ml，再加入甲基橙又用0.1000mol/LHCl溶液滴定至终点，用去23.00ml，此水样中含（）。

A、NaCO3

B、NaHCO3

C、NaOH

D、Hac

“双轨制”是指什么？

回转式烟气换热器的构造？