如图所示，金属导轨上的导体棒ab在匀强磁场中沿导轨做下列哪种运动时，铜制线圈c中将有感应电流产生且被螺线管吸引（   ）

如图示意我国北方地区主要矿产资源和工业分布，读图完成下列各题．

补全对话
A: What animals do you want to see ?
B: ____                       .
A: Why do you like to see pandas?
B: ____ .
A: Really? By the way, do you want to see the elephants in the zoo?
B: ____              .
A: I like to see elephants, too.  Because they can dance.
B: Do you want to be an assistant in the zoo?
A: Well , to work for animals is interesting, but kind of dangerous. I don't like it.
B: ____ ?
A: I want to be a reporter. I can meet many famous (著名的) people.
B: That's great . Thank you.
A: ____           

甲、乙两种物质的溶解度曲线如右图所示，回答下列问题：