人类经历了腊玛古猿、南方古猿、早期智人、晚期智人、直立人等阶段.

左右者，阴阳之（）也；水火者，阴阳之（）也。

如图家庭电路连接正确，各元件均正常，有关说法正确的是：

A.洗衣机接入三孔插座后电灯与洗衣机是串联的

B．洗衣机接入三孔插座能使洗衣机金属外壳接地

C．闭合开关时人接触B点或C点都可能引起触电

D．断开开关时A、B两点都能使测电笔氖管发光

芦花鸡毛色遗传属于（），芦花基因（B）对非芦花基因（b）为显性。芦花母鸡与非芦花公鸡杂交，F1代芦花鸡都是公鸡，非芦花鸡都是母鸡。

Officials in the Midwestern U. S. town of Joplin, Missouri, say the death from Sundays’ big tornado reaches 116 and that search efforts continue for possible survivors trapped in rubble (碎石). Search and rescue teams are conducting their third sweep through the nearly 10 kilometer – long and one – kilometer wide area of destruction left by the tornado. They are working as quickly as possible while weather conditions remain relatively stable. More storms are forecast for the erea.

Joplin Fire Chief Mitch Randles said there are areas with large piles of rubble that might hold survivors. “We are still finding individuals. We did rescue seven individuals from underneath rubble yesterday and , of course, we are also finding dead folks as well.” Said mre folks and that is why we are doing these searches. We want to make every opportunity that we can to find everybody that is in the rubble and that has survived to this point.”

Randles said the current sweep involves a slower pace that previous searches and that he plans a fourth search, possibly on Wednesday, using specially trained dogs. “We are searching every structure that has been damaged or destroyed in a more in-depth manner, “he said.” I have dogs and dog handlers coming from all over the country do help us in that effort.”

Joplin City Manager Mark Rohr said the Red Cross and other volunteer organizations are helping people who were left homeless by the tornado and that the Federal Emergency Management Agency, or FEMA, is on hand to help. “Joplin is a great city. We have suffered a great loss, “said Rohr.” We will recover and we will recover strongly and we have a lot of help and a lot of volunteers to make that easier.”

The tornado that struck Joplin was classified by the Natioonal Weather Service as an F – 4, with winds of more than 300 kilometers per hour. It lasted only  20 minutes, but it killed more that 100 people, injured more than 400 others, and destroyed or heavily damaged some 2,000 homes, businesses, churches and a hospital. Authorities have registered more than 1,700 calls about missing people and they hope to resolve most of those cases soon, as victims are identified and survivors come forth and reunite with loved ones.

This was the worst tornado to strike the United States in 60 years. It was the latest in a wave of violent storms that have swept Midwestern and southern states in recent weeks, leaving more than 300 people dead an causing more than $2 billion dollars in damage.

小题1:The best headline for this newspaper article would be          .

A．Difficulties in the Rescue

B．The Great Loss Brought by the Tornado

C．Search for Survivors After the Disaster

D．Worst Tornado in the USA小题2:The word “resolve” in Para 5 probably means         .

A．cover

B．settle

C．overcome

D．challenge小题3:The number of death caused by the tornado that struck Joplin reached more than       .

A．100

B．300

C．400

D．1,700小题4:From the text, it can be inferred that           .

A．many victims might be under the ruins

B．it was impossible to find out surviors

C．the tornado lasted several weeks

D．the bad weather influenced the rescue greatly

在分配数列中，频数是指（）

A、各组单位数与总单位数之比

B、各组分布次数的比率

C、各组单位数

D、总单位数