平面与正圆锥面截交,当截交线为双曲线时，截平面的位置为()。
A. 平行于圆锥面上一素线
B. 平行于圆锥面上两素线
C. 与圆锥面上所有素线相交
D. 垂直于圆锥轴线
查看答案
立体与投影面的相对位置与投影图的明显性无关。
A. 对
B. 错
Which of the following behavior is considered honesty?
A. Telecom fraud
B. Cheating in examinations
C. Academic misconduct
D. Write a term paper in our own words
In the opening ceremony of the second belt and road forum for international cooperation, President Xi said:“On behalf of the Chinese government and people and in my own name, I ( ) a very warm welcome to you all!”
A. extend
B. extensive
C. expel
D. intend
What consequences dishonesty may not produce?
A. It has an undesirable effect on anyone who practices it
B. Without trust, ordered society would descend into chaos.
C. When honesty disappears, the affirmative, durable bonds of trust are eliminated and we all lose.
D. People will be happier because they will learn something from dishonest behavior.
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