题目

Welcome to our school. You can do a lot of things here. Come and join us. Timetable Sunday 8:30---11:30 Personal Inventions You can see many inventions by the students; you may also bring your own inventions.Monday 19:00---21:00 Space and Man Dr. Thomas West If you want to know more about the universe. Wednesday 19:30---21:00 Modern Medicine Mrs. Lucy Green Would you like to know medical science?Friday 18:30---21:00 Computer Science Mr. Harry Morison from Harvard University Learn to use Windows XP. 21.You may have a chance to introduce your inventions on _________.   A. Sunday    �如图为测定空气中氧气体积分数的实验装置：（1）红磷燃烧的化学反应方程式为_________。（2）红磷熄灭，装置冷却到室温后，打开止水夹，观察到的现象是________。（3）该实验设计依据的N2的性质有________。