皮皮学，免费搜题
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【单选题】
下列属于非实验性研究的特点是( )。A.
设对照组
B.
随机分组
C.
随机抽样
D.
没有人为施加因素
E.
人为设置处理因素
拍照语音搜题，微信中搜索"皮皮学"使用
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皮皮学刷刷变学霸
举一反三
【单选题】As ____________ of World Economic Forum, Dalian and Tianjin have both done a great job.
A.
a symbol of
B.
a promise
C.
historical heritages
D.
host cities
【单选题】Dalian is a great seaside city ________ he visited and had a good impression of.
A.
what
B.
where
C.
which
D.
when
【简答题】Thermal power generation and power generation are the two ways to converted in to electricity (photovoltaic / photosynthesis)
【简答题】最近发展区是苏联心理学家 提出来的。
【单选题】The production of electricity mainly depended on thermal power plants, hydropower stations and nuclear power plants.
A.
电能的生产主要依赖于火电厂、水电站和核电站。
B.
电是火电厂、水电站和核电站生产的主要产品。
【单选题】In the thermal power plant, ___________ like coal and natural gas are burned in furnaces first to _________ water.
A.
fossil fuels; heat up
B.
nuclear power; boil
C.
wind energy ; heat up
D.
solar energy, boil
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