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21-25 Species interdependence in nature confers many benefits on the species involved, but it can also become a point of weakness when one species involved in the relationship is affected by a catastrophe. Thus, flowering plant species dependent on insect pollination, as opposed to self- pollination or wind pollination, could be endangered when the population of insect-pollinators is depleted by the use of pesticides. In the forests of New Brunswick, for example, various pesticides have been sprayed in the past 25 years in efforts to control the spruce budworm, an economically significant pest. Scientists have now investigated the effects of the spraying of Matacil, one of the anti-budworm agents that is least toxic to insect-pollinators. They studied Matacil’s effects on insect mortality in a wide variety of wild in A. Species interdependence is a point of weakness for some plants, but is generally beneficial to insects involved in pollination. B. Efforts to control the spruce budworm have had deleterious effects on the red-osier dogwood. C. The use of pesticides may be endangering certain plant species dependent on insects for pollination. D. The spraying of pesticides can reduce the fecundity of a plant species, but probably does not affect its overall population stability. [多选题]反滤层的材料为碎石、卵石或小砾石，其厚度不能为( )
A.A.20cm以上 B.B.10～15cm C.C.15～20cm D.D.10cm以上 [多项选择]1993年底，中国国民经济信息化的起步工程——“三金工程”正式启动，所谓“三金工程”，即___。
A. 全桥工程 B. 全关工程 C. 全卡工程 D. 全智工程 [判断题]报告义务人为重大信息内部报告的第一责任人,负有敦促本部门或单位信息收集、整理的义务以及向本行董事长、董事会秘书及本行董事会办公室报告其职责权限范围内所知悉的重大信息信息的义务
A.正确 B.错误 [单项选择]“格”即（）式摔跤，是第八届全国少数民族传统体育运动会民族式摔跤的正式比赛项目。
A. 蒙古族 B. 苗族 C. 彝族 [多选题]电能计量装置包含（ ( ) ）。
A.各种类型电能表 B.计量用电压互感器 C.计量用电流互感器 D.电能计量箱 [多选题]关于伸缩区叙述正确的有( )。
A.由2～4节标准轨组成 B.接头必须使用不低于10.9级螺栓 C.长度不得短于50 m D.螺栓扭矩应保持在700～1100N·m [判断题]电容器外置熔断器管体系用来装设熔丝，并起绝缘隔离与防护用，金属管帽作为防爆与安装连接用，在小电流规格还起到与熔体对接导电的作用。
A.正确 B.错误 我来回答: 提交
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