某体校准备在甲乙两位射箭爱好者中选出一人参加集训,两人各射了5箭,他们的总成绩（单位：环）相同,小宇根据他们的成绩绘制了尚不完整的统计图表,并计算了甲成绩的平均数和方差（见小宇的作业）．

甲、乙两人射箭成绩统计表

（1）a=　_________　,=　_________　；
（2）请完成图中表示乙成绩变化情况的折线；
（3）①观察图,可看出　_________　的成绩比较稳定（填“甲”或“乙”）．参照小宇的计算方法,计算乙成绩的方差,并验证你的判断．
②请你从平均数和方差的角度分析,谁将被选中．

下列不属于物质属性的是(     )

    Teachers say buying homework answers online is not many in schools, but an interview with school students shows only 10% are willing to finish their holiday homework by themselves.
    Their main complaint is that the homework is too much for them to finish.
    “As far as I know, many of my students have to go to all kinds of training classes during the holiday. These take away much of their time for doing homework.”
    But as for the parents  who are sending their children to these training classes  they also say they've got no choice. Here's a view from a student's father.
    "All the other kids in the neighborhood are learning extra things. You know parents sometimes compare their kids. I'm afraid my kid will be less successful than the others in the future."
    In order to do with this situation of students copying each other's homework, some schools have even dropped the idea of holiday homework. Instead, they organize some interesting outdoor activities.
     Educational experts say students love to learn through games or activities that they can be a part of. They suggest schools drop the current (目前的）homework format (设计)，and turn to homework that encourages kids to get involved (参与).This way, they would no longer want to copy from each other or buy answers through the Internet.
    Answer the following questions according to what you read.

①中国古代历史上唯一的女皇帝____统治时期形成“政启开元，治宏贞观”的盛世局面。

②“两弹一星”是对原子弹、氢弹和人造卫星的简称。邓稼先被称为____。

③1973年，袁隆平育成____，被称为“东方魔稻”。