问题
单项选择题
The original equilibrium position is stable when().
A.metacentric height is positive
B.metacentric radius is positive
C.KG exceed maximum allowable limits
D.Free surfaces are excessive
答案
参考答案:A
The original equilibrium position is stable when().
A.metacentric height is positive
B.metacentric radius is positive
C.KG exceed maximum allowable limits
D.Free surfaces are excessive
参考答案:A
Teenagers in England do many of the same thi ![]() How do teenagers in England spend their free time and holidays ? Let’s follow Sally , a British teenager , and spend five days with her during her school holiday .
A. In the morning . B. In the afternoon . C. At lunch time . D. In the evening . 2. Which of the foll ![]() A. She went swimming . B. She went out for breakfast . C. She read books . D. She went shopping . 3. How many times did Sally and her mother meet their friends during the five days ? A. Once . B. Twice . C. Three times . D. Four times . 4. According to the passage , it can be inferred that__________. A. a park is the best place to meet a friend B. parents shouln’t leave teenagers alone at home C. teenagers don’t usually do their homework during their school holidays D. surfing the Internet has become an important part of teenagers’ lives |