The Greens are from America. They are now 1 vacation in Beijing. This is their first visit to China. They are going to 2 in China for over two months. They want to visit some big cities, villages and famous places of 3.They want to learn some Chinese and taste some delicious Chinese food, 4.

    Mr. Green is a doctor. He will visit a famous 5 in Beijing. Mrs. Green is a school teacher. 6 teaches English in a middle school. She is going to visit some 7 and village schools. Their daughter, Jane is a middle school student. She studies 8 . She can speak a little Chinese. She would like to make some Chinese friends.

    They are going to 9 a lot of photos in China. When they come back to America, they can show them to their friends. They want Americans 10 more about China.

①实验开始时，先____（选填“通气体”或“加热”），目的是____。B中的现象是____，反应的化学方程式是____。

②小红同学认为进入C中气体是CO₂、CO、H₂O，但上述A~E装置不能验证小红同学的观点，装置正确的连接是A→B→____。

③小兰同学认为为了防止溶液倒吸，本实验停止加热前应先断开B和C的连接，小明同学认为不需要，理由是____。

④实验后小高同学又指出：上图装置的尾气处理E也可以用F装置代替，F装置的作用是____。

已知函数f（x）=x²﹣2ax+2a²﹣2（a≠0），g（x）=﹣e^x﹣$\frac{1}{e^x}$，则下列命题为真命题的是（　　）