在下列四个方程中,X1、X2、X3和X4各代表某种粒子,以下判断中正确的是( )

题型:选择题

问题:

在下列四个方程中,X1、X2、X3和X4各代表某种粒子,以下判断中正确的是(  )

+++3X1+X2+X3+X4

A.X1是α粒子

B.X2是质子

C.X3是中子

D.X4是电子

考点:天然放射现象核反应重核裂变
题型:选择题

识图题

(1)图中人物是谁?生活在什么时期?

___________________________________________________________________________________________

(2)他的思想主张有哪些?

___________________________________________________________________________________________

(3)他有哪些主要成就?

___________________________________________________________________________________________

(4)他的思想对后世有什么影响?

___________________________________________________________________________________________

题型:选择题

若抛物线的准线方程为x=–7, 则抛物线的标准方程为(     )

A.x2=–28y

B.y2=28x

C.y2=–28x

D.x2=28y

题型:选择题
用下列单词的适当形式填空。
be accustomed to,   lay off,   suspect sb.of doing , set about,  as a
whole,  spit at,   to start with,   add up to,  swell with,  keep pace with
1. It's impolite to        others. Besides, it may result in conflicts.
2. The young should       the times, or they'll fall behind others.
3. The bills        100 dollars, which I can't afford.
4. Never       pride when you have made some contributions.
5. I       getting up early. 
6. He told the boys to       making noises.
7. The manager       him       offering false information.
8. The boy       studying at once made his parents happy.
9. He won't win the match.        he lacked experience.
10. His property was sold      , so now he has nothing.
题型:选择题

年功序列工资的优越性。

题型:选择题

跑道中线灯颜色为红白相间的一段是:().

A.从跑道入口到跑道末端

B.从跑道入口后300米到至跑道入口900米

C.从距跑道末端900米到距跑道末端300米

D.从距跑道入口900米到距跑道入口300米

更多题库