一矩形闭合线圈绕垂直于匀强磁场并位于线圈平面内的固定轴转动，下述说法正确的是（   ）

已知m+n=8，mn=15，求m²﹣mn+n²的值．

Woman：Can I help you ?

Anna：Yes, please .I need a new pants for school.

Woman：Ok. What colour do you want?

Anna：Blue.

Woman：How about this one?

Anna：It looks nice. How much are they?

Woman：They are fifty-four yuan.

Anna：I'll take it. How much are those yellow shoes?

Woman：Thirty-five yuan.

Anna：Great! I'll take them.

Woman：Here you are.

Anna：Thank you!

Woman: You're welcome.

 氧元素是地壳中含量最高的元素，请回答下列问题

（1）画出氧原子结构示意图　____ 　．

（2）元素周期表中氧元素的信息如图所示，从图中能直接获得的信息是____ ．

A．氧元素属于非金属元素

B．氧原子的核内的质子数为16

C．氧元素有O₂和O₃两种单质

（3）图2是硫化氢（H₂S）在氧气中不完全燃烧反应的微观示意图．

写出该反应的化学方程式____ ，该反应属于____（填基本反应类型）．