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【单选题】
拥挤效应，是指种群增长过程中随着密度增加而使种群增长速度降低的现象。如果环境条件是无限的，种群应以指数形式增长，而实际上咋有限环境中都呈逻辑斯蒂形式（先增长后下降。类似抛物线）增长，这想着的差距从环境的角度找到原因时被称为环境阻力；从种群自身找原因时被称为拥挤效应。根据上诉定义，下列体现了拥挤现象的是（）。A.
某地区采取优惠政策吸引高新技术工业企业落户，随着企业的逐渐增多，工人开始供不应求，不少企业出现用工荒，今儿减产甚至停产
B.
区政府牵头将附近的中小建材厂集中起来，以实现规模经济，却不料这些建材厂为了竞争订单互相压价，最终导致一些建材厂倒闭
C.
某村镇的农民联合种植枇杷，因其质量好，产量大，许多收购者纷纷慕名前来收购，周围村镇也开始种植枇杷，不就该县成了全国闻名的枇杷之乡
D.
某火车站附近因课流量较大成为小摊贩的集聚地，后因小摊贩越来越多，严重影响周围的交通秩序和卫生环境，被城市管理执法部门取缔
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【单选题】I believe that is a proper standard by which to judge people even though I still don't know ____ a good heart is.
A.
what
B.
which
C.
where
D.
how
【简答题】完形填空 A piece of advice that I often receive is 'as long as you do your best'. I believe that this is good advice _ 1 __ it tells me that they trust my __ 2 __ and will respect my decisions, even if t...
【单选题】I believe that he is a____ person, so he will succeed in time. [ ]
A.
talented
B.
talent
C.
gift
D.
decided
【简答题】阅读理解。 I believe that my country, Poland, is a perfect example for a place where food is particularly important. When we were little children, we began to understand how much a loaf of bread meant to o...
【简答题】I believe that my country, Poland, is a perfect example for a place where food is particularly important. When we were little children, we began to understand how much a loaf of bread meant to our par...
【单选题】Now that I am older, I believe that is a proper standard ______ judge people.
A.
by which
B.
from which we
C.
by which to
D.
from which to
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