据上海证券交易所的相关规定，单个会员管理的多个集合资产管理计划由同一托管机构托管，必须使用不同的席位。 ( )
参考答案：错
Great changes______in the mountain village in the last few years.For example,electric lamps______of oil ones.
A．have been taken place;have taken place
B．have taken place;have taken the place
C．have taken the place;have taken place
D．have taken the place;have taken the place
电离层特点是（）①对频率高的无线电波吸收大，因此传播距离近②对频率低的无线电波吸收大，因此传播距离近③电离层浓度高，静区大④电离层浓度低，静区大⑤通常白天电离层浓度高，晚上低⑥晚间.白天电离层浓度不变
A.②③⑤
B.③⑤⑥
C.①③⑤
D.②④⑥
