皮皮学，免费搜题
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【单选题】
你认为下面哪句话，应该出现在摘要的第一句A.
Innovation, defined as creativity with a purpose, is widely considered to be the engine of scientific progress.
B.
However, the recent introduction of cleaner technologies in the UK has led to reductions in the emissions of nitrogen oxides, with concomitant decreases in N deposition.
C.
We find that ozone production occurs at lower NOx and much larger VOC concentrations than does its summertime urban counterpart, leading to carbonyl (oxygenated VOCs with a C = O moiety) photolysis as a dominant oxidant source.
D.
It is our hope that this information will aid and encourage researchers to implement gene-targeting techniques into their research program.
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皮皮学刷刷变学霸
举一反三
【单选题】以下不属于发动机拆装作业技术要求的是( )。
A.
拆下空气滤清器，更换滤芯
B.
更换机油粗、细滤清器密封圈应完好有效，油道(喷孔)畅通，性能良好
C.
清除火花塞积炭，矫正电极间隙
D.
汽缸盖螺栓齐全完好，其拧紧扭矩符合车型技术要求
【多选题】对于拆卸和安装燃油滤清器，以下说法正确的是
A.
高热的燃油可能导致烫伤
B.
如果更新燃油滤清器或燃油管路，则在首次起动发动机前必须给燃油系统排气
C.
滤清器外壳上标有箭头显示燃油流动方向
D.
对于奥迪轿车，需用软管专用卡箍钳 VAS 6362