简述流量控制阀的基本功能及基本原理？

One method of dating the emergence of species is to compare the genetic material of related species. Scientists theorize that the more genetically similar two species are to each other, the more recently they diverged from a common ancestor. After comparing genetic material from giant pandas, red pandas, raccoons, coatis, and all seven bear species, scientists concluded that bears and raccoons diverged 30 to 50 million years ago. They further concluded that red pandas separated from the ancestor of today’s raccoons and coatis a few million years later, some 10 million years before giant pandas diverged from the other bears.
Which one of the following can be properly inferred from the passage

A．Giant pandas and red pandas are more closely related than scientists originally thought they were.

B．Scientists now count the giant panda as the eighth species of bear.

C．It is possible to determine, within a margin of just a few years, the timing of divergence of various species.

D．Scientists have found that giant pandas are more similar genetically to bears than to raccoons.

E．(E) There is substantial consensus among scientists that giant pandas and red pandas are equally related to raccoons.

一束激光射到平面镜上，当入射角是55度时，反射角是______度．

急性肝炎时

A．浮肋
B．肋脊角
C．胸骨角
D．腹上角
E．肩胛下区

公民、法人或其他组织向人民法院提起行政诉讼后，无论人民法院是否已经受理，都可以同时申请行政复议。( )

下列有关尖锐湿疣的说法，正确的有（）

A.是一种皮肤粘膜良性赘生物

B.主要通过性接触传染，但也可以通过间接接触传染

C.与生殖器癌的发生密切相关

D.潜伏期约为1～8月，平均3月

E.包皮过长或白带过多的人易受感染或复发