There is a park near my house. It's very big and beautiful. It's fine today. I am in the park now. There is a book shop on my left. Some people are reading books. On my right, there is a long river. There are many flowers and trees near the river. There are some boats on the river. Some children are rowing boats. There is a hill in the park. I'm going to climb the hill. I like the park very much.

（2015•莱芜）将数字2.03×10^﹣3化为小数是（　　）

下图实验是测定空气中氧气的含量。关于该实验的下列说法中，错误的是