如图是实验室里一瓶标签破损的无色液体，某同学取出少量液体于试管中，加入少量黑色固体，产生大量气泡，则下列推测正确的是（　　）

①若加入的黑色粉末为铁粉，则该无色液体为盐酸；

②若加入的黑色粉末为二氧化锰，则该无色液体为过氧化氢；

③若加入的黑色粉末为二氧化锰，则该无色液体为水；

④若加入的黑色粉末为铁粉，则该无色液体为硫酸．

A．①③

B．②④

C．②③④

D．①②③④

• A. Is that clear
• B. Can it do some washing
• C. Why do you think it is useful
• D. It appeared several centuries ago, didn’t it
• E. Will robots be the same as people
• F. What is it
• G. Could you please tell me more about robots
  A: Today we are going to talk about a great invention. It looks like a human being. (61)
  B: It’s a robot. (62)
  A: Of course not. The first robot was invented in 1921.
  B: (63)
  A: Sure. They can take the place of humans to do some boring work. They can also do a lot of dangerous work instead of humans.
  B: (64)
  A: No. Robots can do a lot of work instead of people in many ways, but people wouldn’t be replaced by robots. (65)
  B: We get it.