标准头穴线的数目是（）。 A.15条 B.18条 C.10条 D.14条 E.16条

会员制期货交易所各专门委员会对理事会负责，其职责、任期和人员组成等事项由理事会规定。（）

A new study finds that the animal known as man’s best friend can also be a good friend to the heart. Researchers in California say they have found that even just a short visit with a dog helped ease the worries of heart patients.               

The study divided the patients into three groups. In Group A, a dog and a person visited each patient for twelve minutes. Patients in Group B received just a human visitor for twelve minutes. And members of Group C received no visitor, human or canine(犬的).

The dogs would lie on the hospital bed so the heart patients could touch them. The researchers say some patients immediately smiled and talked to the dog and the human visitor. Dogs, in her words, “make people happier, calmer and feel more loved.”

The researchers examined the patients before, during and after the visits. They measured stress levels based on blood flow and heart activity. They say they found a twenty-four percent decrease in the group visited by both a dog and a person. They reported a ten percent decrease in the group visited by a person only. There was no change in the patients without any visit. These patients, however, did have an increase in their production of the hormone epinephrine (epinephrine肾上腺素). The body produces epinephrine during times of stress.

The increase was an average of seven percent. But the study found that patients who spent time with a dog had a seventeen percent drop in their levels of epinephrine. Patients visited by a human but not a dog also had a decrease, but only two percent.

小题1:The author believes that _______.  

A．the dog can take the place of most medicines

B．the dog is the most popular pet for man

C．the findings of the research cannot be trusted

D．visits by a human work better than visits by a dog小题2:Which of the following best shows the stress level changes in the groups of patients? BACC

小题3:From the research findings we may conclude that _______.

A．the less the body produces epinephrine, the better

B．the longer a visit lasts, the happier the patient should be

C．the patients enjoyed the dogs’ company more than the human visitors’

D．it’s impossible for heart patients to recover without dogs’ visits小题4:Which of the following is the best title for the passage?

A．Worried Heart Patients

B．Epinephrine and Stress

C．Good Friend to the Heart

D．Three Groups of Patients

保存文物特别丰富并且具有重大历史价值或者革命纪念意义的城市，由国务院核定公布为历史文化名城。( )

识记的内容遗忘最快发生在识记后的（）。

A.第1天

B.第2天

C.第3天

D.第4天

E.第5天

已知△ABC中，AB=AC，点D是△ABC外接圆劣弧

上的点(不与点A，C重合)，延长 BD至点E。

(1)求证：AD的延长线平分∠CDE；

(2)若∠BAC=30°，△ABC中BC边上的高为

，求△ABC的外接圆的面积S。