根据句意和首字母填入恰当的词 

1. We were completely in the d __    about his movements.    

2. Her answer is r_____.    

3. If you want to s  __    . money, you had better buy second-hand books.    

4. I w____ about the exam tomorrow because it's very difficult.  

5. I used to eat c____ all the time. It's bad for my teeth.

T℃，向5.0 L恒容密闭容器中充入1.0 molSO₃气体，发生反应：2SO₃(g) 2SO₂(g)+O₂(g)

△H="+196" kJ/mol，一段时间后达到平衡，测得此过程中从外界共吸收了19.6 kJ的热量。当温度度不变时，改变某一条件，下列结论正确的是