读图，回答以下问题。

下图所示的实验操作不正确的是(    )

根据下面的对话情景，在每个空白处填上—个适当的句子，使对话的意思连贯、完整。
A:I have a piece’ of good news to tell you , May?
B：Oh，____ ?
A: A new library has been open in our city, and there are many books there.
B: Really? ____ ?
A: It is open at 8:00 in the morning and closed at 6:00 in the afternoon.
B: ____ ?
A:  Yes, I went there yesterday
B: ____ ?
A: It’s in No. 7 building,  Center Street. ____ ?
B:Yes. I want to go there tomorrow.  Would you like to go with me?
A: Of course. Let’s meet at our school gate tomorrow.
B：OK. See you.
A: See you.

将一定质量的氯酸钾与二氧化锰混合加热，变量y随加热时间的变化趋势如图，则变量y可表示的是（　　）

孝感地区的房屋多为坐北朝南且屋顶坡度大，这体现了（　　）