China is now facing a very serious environment problem, that is Sandstorm (沙尘暴)．Now  this problem becomes worse and worse．

330,000-ton sand fell on Beijing on April 18^th, 2006．This is the tenth instance(情况) of sandstorms in northern China this year and the eighth in Beijing．Most of the sand in Beijing comes from Inner Mongolia．The situation this year is worse than the past two years．

People had to clean the dust-covered(灰尘湮没的) roads by washing instead of sweeping．The sandstorms this year could appear because of high temperature, long droughts(干旱) and frequent(经常发生的) cold air．

From March, the rainfall in northern China is about 75% of the average figure (平均数) in the past few years and some parts reported rainfall to be about 20% of the average figure in the past few years．

Cold air is frequent (惯常的)in March and April in northern China and it brings strong wind and sandstorms to the areas．

1．The environment problem becomes               

A．more and more                                      B．worse and worse

C．drier and drier                                            D．less and less

2．How many tons of sand fell on Beijing on April 18th,2006？

A．33,000             B．333,000           C．330,000            D．3,300

3．How did people clean the dust-covered roads?

A．By sweeping                                           B．By rainfall

C．By sweeping and washing                          D．By washing

4．          causes the sandstorms this year besides (除)high temperature, long droughts．

     A．Frequent cold air．                                B．Rainfall

C．Heavy traffic                                           D．Sand

5．Sandstorms often appear in northern China in           ．

A．January and February                                 B．March and April

C．Summer                                              D．Autumn

小明利用如图甲所示的电路探究电流跟电阻的关系。已知电源电压为6V且保持不变，实验用到的电阻阻值分别为5Ω、10Ω、15Ω、20Ω、25Ω。

⑴请根据图甲将图乙所示的实物电路连接完整(导线不允许交叉)。
⑵实验中将5Ω电阻换成10Ω电阻后，应将滑动变阻器的滑片P向______端移动（左/ 右），移动滑片的目的是___________________。正确操作后，记下电流表的示数，得到电流Ｉ随电阻R变化的图象如图乙所示，由图象可得出的结论是：_________________________。
⑶为完成整个实验，应该选取最大阻值不小于      Ω的滑动变阻器。
⑷实验过程中，如果出现了电流表示数为0，电压表示数接近6V，电路发生的故障可能是_____________________。

话题作文：2011年3月11日，日本发生了里氏9.0级地震，整个日本东北部地区受灾严重。假如你是一名叫李刚的学生，请给日本的中学生写一封信，表示对他们的关心，并鼓励他们要勇于战胜困难，树立信心，努力学习，迎接更加美好的明天。

 

话题作文：2011年3月11日，日本发生了里氏9.0级地震，整个日本东北部地区受灾严重。假如你是一名叫李刚的学生，请给日本的中学生写一封信，表示对他们的关心，并鼓励他们要勇于战胜困难，树立信心，努力学习，迎接更加美好的明天。

 

话题作文：2011年3月11日，日本发生了里氏9.0级地震，整个日本东北部地区受灾严重。假如你是一名叫李刚的学生，请给日本的中学生写一封信，表示对他们的关心，并鼓励他们要勇于战胜困难，树立信心，努力学习，迎接更加美好的明天。