图示为一列沿x轴负方向传播的简谐横波,实线为t=0时刻的波形图,虚线为t=0.6

题型:不定项选择

问题:

图示为一列沿x轴负方向传播的简谐横波,实线为t=0时刻的波形图,虚线为t=0.6 s时的波形图,波的周期T>0.6 s,则

[ ]

A.波的周期为2.4 s

B.在t=0.9 s时,P点沿y轴正方向运动

C.经过0.4 s,P点经过的路程为4 m

D.在t=0.5s时,Q点到达波峰位置

考点:波的图像
题型:不定项选择

阅读下面短文,用括号内所给动词的适当形式填空(必要时可加情态动词或助动词)。

      Almost every child in cities has the chance to go to school, but not all children in the villages are so lucky.

There is a girl (1) ______ (call) Xiao Lian, she is ten years old and lives in a small village. When she was seven,

she (2) ______ (want) to go to school. But she could not, because her family was too poor (3) ______ (afford)

the school for her, so her parents had to keep her at home. Instead of (4) ______ (study). Xiao Lian looked after

her brother and (5) ______ (work) in the fields every day. Then Hope Project heard about Xiao Lian. It agreed to

help her to go to school. Her wish of study came true and now she (6) ______ (study) in school. 

      Unluckily there are many thousands of children who can not go to school. You can join in Hope Project and

help these children. You know all the good work (7) ______ (need) money. Hope Project needs your help. If you

(8) ______ (give) Hope Project¥300 each year, it can pay for one child to go to school for a whole year. With

more money, Hope Project (9) ______ (build) new schools, buy good desks, chairs, blackboards and books.

Let's (10) ______ (help) the children together and give them a chance have a good start in life.

题型:不定项选择

列车运行速度不超过120km/h的区段,预告信号机与其主体信号机的安装距离不得小于()。

A、800m

B、900m

C、1000m

D、1100m

题型:不定项选择

( )的主要目的是评价影响企业目前和今后发展的关键因素,并确定在战略选择步骤中的具体影响因素。

A.战略评价
B.战略分析
C.战略决策
D.战略实施

题型:不定项选择

在货运事故处理系统中,案卷自初次传输时起()内仍未传输成功的应于当日向上级报告,并按规定启用纸质文档处理。

A.1小时

B.12小时

C.24小时

D.48小时

题型:不定项选择

制剂的含量测定首选

A.容量分析法(滴定分析法)
B.生物检定法
C.酶法
D.HPLC法
E.UV法

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