在△ABC中,∠A:∠B:∠C=1:2:3.已知BC=3cm,则AB=_____

题型:填空题

问题:

在△ABC中,∠A:∠B:∠C=1:2:3.已知BC=3cm,则AB=______cm.

考点:勾股定理的逆定理
题型:填空题

根据以下提示,写一篇80词左右的英语短文,介绍你在地震中的一次逃生经历。

要点:

昨天夜里地震来袭时,你正在做家庭作业。

感到整个大楼在摇晃。有些书从书架上落下。

听到一个男人在大声喊叫。

叫醒父母,一起急忙下楼.

地震过后,楼还在那里,人都活着.

要求:1.短文应包括要点中所给信息,各要点均可作适当发挥.

2.行文连贯,书写规范。

3.词数80个左右。短文的开头已经给出,不计入词总数.

I was doing my homework when _______________________________

题型:填空题

第四节:阅读理解(共20小题,每小题2分,满分40分)

阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项。

A

Science Daily -------- Dutch ecologist Roxina Soler and her colleagues have discovered that subterranean(地下的)and above ground herbivorous(食草的)insects can communicate with each other by using plants as telephones. Subterranean insects issue chemical warning signals through the leaves of the plant. Thus, aboveground insects are warned that the plant is already “ occupied”.

In recent years it has been discovered that different types of aboveground insects develop slowly if they feed on plants that also have subterranean residents and vice versa(反之亦然). It seems that a system has developed through natural selection, which helps the subterranean and aboveground insects to communicate with each other. This avoids unnecessary competition.

Through the “green telephone lines”, subterranean insects can also communicate with a third party, namely caterpillars(毛虫). Parasitic wasps(寄生的黄蜂)lay their eggs inside aboveground insects. The wasps also benefit from the signals sent by the leaves, The communication between subterranean and aboveground It is still not clear how widespread this phenomenon is.

This research was carried out at the Netherlands Institute for Ecology by Roxina Soler, Jeffrey Harvey, Martijn Bezemer, Wim van der Putten and Louise Vet. was funded by the Free Competition of NOW Earth and Life Sciences.

41. After finding a plant occupied by root-eating insects, aboveground insects will usually ________.

A. send out warning signals

B. choose to leave the plant

C. fight with the root-eating insects

D. compete with them for the same plant

42. Aboveground insects will develop more quickly if their food plants _______.

A. have more green leaves

B. get more water and sunlight

C. are often visited by parasitic wasps

D. are not occupied by root-eating insects

43. The underlined part “a third party” in Paragraph 4 refers to ______.

A. caterpillars               B. root-eating insects    

C. parasitic wasps          D. aboveground insects

44. What is the best title for the passage ?

A. Insects use plants as “telephones”

B. How do animals avoid competition

C. The living habit of different insects

D. Communication between different insects

题型:填空题

某灯泡额定电压是24V,正常发光时灯丝的电阻为16Ω,则灯泡正常发光时的电流是______A.若想使该灯泡在电源电压为36V的电路中正常发光,可在电路中串联一个阻值为______Ω的电阻.

题型:填空题

“善待老人,就是善待明天的自己”,“不能在丢垃圾时,丢了自己的脸”。这些随处可见的公益广告悄然给社区居民的言行带来可喜的变化。这体现了()

①文化影响人们的交往行为和交往方式

②文化的精神力量可以转化为物质力量

③文化通过特定的文化环境和文化活动影响人

④文化潜移默化地决定着人的发展方向

 

A.①②

B.①③

C.②④

D.③④

题型:填空题

建设占用土地,涉及农用地转为建设用地的,可以办理农用地转用审批手续。

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