强度较大的太阳风暴会造成地球上高频无线电通讯的中断，产生这一_爱下问搜题

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问题选择题

强度较大的太阳风暴会造成地球上高频无线电通讯的中断，产生这一现象的主要原因是

A．地球大气层中的臭氧层空洞扩大使太阳辐射迅速增强

B．太阳耀斑爆发引起地球大气层的电离层扰动

C．太阳黑子增多造成地球磁场紊乱，产生“磁暴“

D．太阳系中的天体在太阳风暴到来时对地球引力加强

答案

答案：B

本题考查太阳活动对地球的影响。太阳活动对地球的影响：引起电离层挠动，影响无线电短波通讯；产生磁暴现象；产生极光现象；对地球气候产生影响，太阳黑子活动周期往往与地球各地年降水量变化周期有相关性。所以本题选择B选项。

解答题

已知函数f(x)=5sinxcosx+5

；
（Ⅰ）确定函数f（x）的单调增区间；
（Ⅱ）当函数f（x）取得最大值时，求自变量x的集合．

完形填空

Do you know why different animals or pests(害虫) have their special colors? Colors in them seem to be mainly used to    1   themselves.
Some birds like eating locusts(蝗虫), but birds cannot    2  catch them. Why? It is because locusts change their   3   with the change of the colors of crops. When crops are green, locusts look    4 . But as the harvest time comes, locusts change into the same brown color    5  crops have. Some other pests whose colors are   6   plants are easily found and eaten by   7  . So they have to hide themselves for lives and appear only   8  .
If you    9 animals’ life, you’ll find the main use of colors is to protect    10  . Bears, lions and other animals  11  quietly through forests. They cannot be easily seen by hunters   12  their colors are much like the trees.
Colors are useful not only on the land, but also in the   13 . A kind of fish can   14 a kind of black liquid(液体) when they face danger. The liquid spreads over quickly, so they cannot be found by their enemies and can quickly swim away. That is   15 they can live safely though they are not strong at all. So colors are really useful to animals.

D．differently

A．different from

D．opposite with

A．in the morning

D．in the daytime