题干

构建、网络是一种重要的学习方法.如图是某同学构建的有关氧气的获取和性质的知识网络图.请根据该图,回答有关问题:

上一题 下一题 0.0难度 选择题 更新时间:2017-02-25 04:04:12

答案(点此获取答案解析)

同类题5

When it was his turn to deliver his speech, ______, he walked towards the microphone.