HTTPS使用的是（）

A:SSH的HTTP B:Security的HTTP C:TCP的HTTP D:SSL的HTTP

图是蜘蛛结网过程示意图，一只蜘蛛先以为起点结六条线后，再从线上某点开始按逆时针方向依次在…上结网，若将各线上的结点依次记为1、2、3、4、5、6、7、8、…，那么第200个结点在（ ）

A:线上　 B:线上 C:线上　 D:线上

如图，两根铁棒直立于桶底水平的木桶中，在桶中

加入水后，一根露出水面的长度是它的，另一根露出水面的长度是它的.两根铁棒长度之和为55 cm，此时木桶中水的深度是 cm.

陈老师要为他家的长方形餐厅(如图)选择一张餐桌，并且想按如下要求摆放：餐桌一侧靠墙，靠墙对面的桌边留出宽度不小于80cm的通道，另两边各留出宽度不小于60cm的通道.那么在下面四张餐桌中，其大小规格符合要求的餐桌编号是　　　　(把符合要求的编号都写上).

 ①②③④

如图，在方格纸中，将图①中的三角形甲平移到图②中所示的位置，与三角形乙拼成一个矩形，那么，下面的平移方法中，正确的是（ ）

A:先向下平移3格，再向右平移1格 B:先向下平移2格，再向右平移1格 C:先向下平移2格，再向右平移2格 D:先向下平移3格，再向右平移2格

某文具店销售供学生使用的甲、乙、丙三种品牌的科学计算器，共销售台，其中

甲种品牌科学计算器销售台.

请根据相关信息，补全各品牌科学计算器销售台数的条形图和扇形图.

图中是一副三角板，45°的三角板Rt△DEF的直角顶点D.恰好在30°的三角板Rt△ABC斜边AB的中点处，∠A.=30^o，∠E.= 45^o，∠EDF=∠ACB=90 ^o ，DE交AC于点G.，GM⊥AB于M..

（1）如图①，当DF经过点C. 时，作CN⊥AB于N.，求证：AM=DN.

（2）如图②，当D.F.∥AC时，DF交BC于H.，作HN⊥AB于N.，（1）的结论仍然成立，请你说明理由.

证明：（1）∵∠A=30°，∠ACB=90°，D是AB的中点.

     ∴BC=BD， ∠B=60°

     ∴△BCD是等边三角形.

     又∵CN⊥DB，

     ∴

     ∵∠EDF=90°，△BCD是等边三角形.

     ∴∠ADG=30°，而∠A=30°.

     ∴GA=GD.

∵GM⊥AB

∴

又∵AD=DB

∴AM=DN  

（2）∵DF∥AC

∴∠1=∠A=30°，∠AGD=∠GDH=90°，

∴∠ADG=60°.

∵∠B=60°，AD=DB，

∴△ADG≌△DBH

∴AG=DH，

又∵∠1=∠A，GM⊥AB，HN⊥AB，

∴△AMG≌△DNH.

∴AM=DN .  

某班5位同学参加“改革开放30周年”系列活动的次数依次为，则这组数据的众数和中位数分别是（ ）

A: B: C: D:

在北京奥运会上获得比赛前三名的选手都将挂上既体现奥运理念，又体现中华民族特色的奖牌――用一种玉石制作然后分别镀上金、银、铜而成的奖牌。刘星是个爱动脑筋的孩子，当他得到一小块制作奥运奖牌余下的玉石材料后，立即着手利用家里的弹簧秤测这种材料的密度。请你和刘星一起来完成测量过程。（g取10N/kg）

（1）右图甲所示用细线拴住玉石块，用弹簧秤测出其所受重力，这时弹簧秤示数是_______N，从而可计算出玉石块的质量。

（2）如图乙所示让玉石块完全浸入水中，从图中弹簧秤的示数可计 算出玉石块所受的浮力是__________N。

（3）利用以上测量数据可计算出玉石块的密度______kg/m³。

（每空1分，共3分）3.6　0.8　4.5×10³

Maybe ten-year-old Elizabeth put it best when she said to her father, "But, Dad, you can't be healthy if you're deaD."

Dad, in a hurry to get home before dark so he could go for a run, had forgotten to wear his safety belt-- a mistake 75% of US population make every day. The big question is why.

There have been many myths about safety belt ever since their first appearance in cars some forty years ago. The following are three of the most common.

Myth the Number One: It's best to be "thrown clear" of a serious accident.

Truth: Sorry, but any accident serious enough to "throw you clear" is able going to be serious enough to give you a very bad landing. And chances are that you'll have traveled through a windshield（挡风玻璃）or door to do it. Studies show that chances of dying after a car accident are twenty-five times in cases where people are "thrown clear".

Myth Number Two: Safety-bets "trap" people in cars that are burning or sinking in water.

Truth: Sorry again, but studies show that people knocked unconscious（昏迷）due to not wearing safety belts have a greater chance of dying in these accidents. People wearing safety belts are usually protected to the point of having in these accidents. People wearing safety belts are usually protected to the point of having a clear head to free themselves from such dangerous situation, not to be trapped in them.

Myth Number Three: Safety belts aren't needed at speeds of less than 30 miles per hour（mph）.

Truth: When two cars traveling at 30 mph hit each other, an unbelted driver would meet the windshield with a force equal to diving headfirst into the ground from a height of 10 metres.

41. Why did Elizabeth say to her father, "But, Dad, you can't be healthy if you're dead"?

A. He was driving at great speeD.

B. He was running across the street.

C. He didn't have his safety belt on.

D. He didn't take his medicine on timE.

42. The reason father was in a hurry to get home was that he __________.

A. wasn't feeling very well B. hated to drive in the dark

C. wanted to take some exercise D. didn't want to be caught by the people

43. According to the text, to be "thrown clear" of a serious accident is very dangerous because you ________.

A. may be knocked down by other cars.

B. may get serious hurt thrown out of the car

C. may find it impossible to get away from the seat

D. may get caught in the car door

44. Some people prefer to drive without wearing a safety belt because they believe _______.

A. the belt prevents them from escaping in an accident

B. they will be unable to think clearly in an accident

C. they will be caught when help comes

D. cars catch fire easily

45. What is the advice given in the test?

A. Never drive faster than 30 miles an hour.

B. Try your best to save yourself in a car accident.

C. Never forget to wear the safety belt while driving.

D. Drive slowly while you're not wearing a safety belt.

CCBAC