观察方格中图形的变化，并回答问题。

如果发现散点图中所有的样本点都落在一条斜率为非0实数的直线上，则R²=____ 

在下列生态系统中，自动调节能力最大的是（　　）

读陕西省地形略图，完成下题。

从方框中的A-G选项中选择适当的句子将对话补充完整,有两个多余选项。

A. No, it isn't. B. Yes, it is. C. They are her pencil case and baseball. D. Where is her hat? E. It's on the chair. F. What's this? G. It's a baseball.

A: Hi, Grace! ____
B: It's a photo of Anna's room.
A: ____
B: It's on the bed.
A: Is her alarm clock on the bed?
B: ____ It's on the desk.
A: Well, where is her backpack?
B: Look! ____
A: And what are those on the floor?
B: ____ The pencil case is red, and the baseball is white.