Minimizing the environmental damage that new roads cause is generally regarded as a good thing. But to do that, it helps to understand just how new roads cause the damage of which they are accused.
Recently, a group of researchers led by Dr Gonzalez conducted an experiment which shows what ecologists have long suspected, but never been able to prove: that immigration is good for the health of animal populations.
A road destroys only a small part of the habitat it traverses, and thus annihilates just a few local populations of creatures. So the argument that road-building itself is bad for biodiversity is not self-evidently correct. Those who nevertheless hold this view usually point to a piece of ecological theory called "meta-population dynamics". This says that apparently separate local populations of animals are, in fact, parts of much larger populations connected via migration.
According to this theory, when a local population flounders &mdas
A. does more harm than good to animal populations
B. keeps local animals and insects healthy
C. has little effect on animal populations
D. helps local animal populations to grow

查看答案

[单项选择]新鲜血清中主要含下列哪一组凝血因子( )
A. 因子Ⅶ和因子Ⅹ
B. 因子Ⅴ和因子Ⅷ
C. 因子Ⅱ，Ⅴ，Ⅶ，Ⅹ
D. 因子Ⅰ，Ⅲ，Ⅴ，Ⅶ
E. 因子Ⅶ，Ⅷ，Ⅴ，Ⅱ

查看答案

[多选题]班组长在日常管理工作中可以根据不同的情况,运用语言沟通和非语言沟通的恰当形式。比如语言沟通中的（）等，非语言沟通中的面部表情、眼神和身体姿态等不同形式，逐步掌握并建立无障碍语言沟通,提高班组管理中的沟通效率。
A.语体
B.语速
C.语调
D.技巧

查看答案

[名词解释]“奥勃洛摩夫性格”

查看答案

[判断题]进路表示器在其主体信号机开放时点亮，用于区别进路开通方向或双线区段反方向发车，可以独立构成信号显示。(技规)
A.正确
B.错误

查看答案

[单项选择]现浇钢筋混凝土无梁楼板的混凝土工程量应按（）计算。
A. 板的体积
B. 板的体积乘以1.22的系数
C. 板和柱帽体积之和
D. 不同板厚以水平投影面积

查看答案

[多选题]提升（顶升）抱杆时，要加装不少于（　　）腰环，腰环固定钢丝绳应呈（　　）并收紧，同时应设专人指挥。
A.A.两道
B.B.三道
C.C.水平
D.D.垂直

查看答案

[判断题]击球次序的排列，是按队员的击球能力、特点和中球率以及双方的实力等情况来考虑安排的，是战术的组成部分，其中充满了战术意义。

查看答案

[单项选择]操作手法的走向（）是美容按摩的基本原则。
A. 由下至上
B. 由上至下
C. 由外至内
D. 由两边至中间

查看答案

[单项选择]某投资者以25万元购买了一个商铺2年的经营权，第一年净现金流量可能为：22万元、18万元和14万元，概率分别为0.2、0.6和0.2；第二年净现金流量可能为：28万元、22万元和16万元，概率分别为0.15、0.7和0.15，若折现率为10%。问该购买商铺投资净现值的期望值为 ( )万元。
A. 25
B. 35
C. 40
D. 45

查看答案

我来回答:

提交