电阻R1=160Ω,R2=40Ω,两者串联后,在其两端加200V电压时,R2上的压降等于40V。
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Exercise 1Directions: You will hear an interview of Chinese astronauts. Choose the best answer to each question.1.Which of the following statement is false?
A. It’s difficult to dock two space crafts together
B. Astronauts should do simulations many times before docking
C. Astronauts should practice two years before docking
D. Astronauts should practice two hours before docking
2. Which of the following is not included in the training of astronauts?
A. Cross training.
B. Physical training.
C. Psychological training.
D. Team testing.
3.Which of the following is not considered in the selection of astronauts?
A. Certain height.
B. Certain appearance.
Certain characteristics .
D. Physical and psychological qualities.
4. What are the models in the video for?
A. Tiangzhou 1 and Shenzhou spacecraft .
B. Tianzhou 2 and Shenzhou spacecraft .
C. Tiangong 1 and Shenzhou spacecraft.
D. Tiangong 2 and Shenzhou spacecraft.
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