Xác định độ cứng khuôn dập bằng thép C80 nếu biết khuôn đem lên máy thử độ cứng Rockwell, lực thử 150KG, mũi thử kim cương, số liệu trên thang đo C của máy là 55? a. 55 HRA b. 55 HRB c. 150HRC d. 55HRC

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Question 13. - “May I go out for just a while?” “_________” A. It’s a nice day! B. That’s great! C. Go ahead! D. Yes, you could! Question 14. Tidal waves are the result of an abrupt shift in the underwater _________ of the earth. A. movement B. moment C. pollution D. celebration Question 15. Thousands of lives were saved _________the scientists had warned them about the tsunami. A. although B. however C. because D. therefore Question 16. Jane often drinks coffee in the evening, _________? A. doesn’t Jane B. does not she C. does she D. doesn’t she Question 17. I suggest that you _________buy a present for her on her birthday. A. may B. can C. should D. will Question 18. Yoko feels_________again after her illness but she still cannot work hard A. strengthen B. strength C.strongly D. strong Question 19. - “Rita, I’d like _________ a friend of mine, Lucie.” - “Pleased to meet you, Lucie!” A. to meet you B. introduce you to C. you see D. you to meet Question 20. The match takes place _________ Saturday afternoon this week. A. of B. on C. after D. to Question 21. She is the girl _________ eyes are beautiful. A. her B. whom C. whose D. those Question 22. If I were rich, I _________around the world. A. travel B.will travel C. would travel D. traveled Question 23.The entrance examination _________from 3rd to 4th June,2021 . A. to held B. held C. hold D. will be held Question 24 . I'm very _________that you have spoiled this historical site. A. thoughtful B. grateful C. excited D. disappointed