依据《中华人民共和国水污染防治法》,建设单位在()新建、改建、扩建排污口的,应当取得水行政主管部门或者流域管理机构同意。
A.江河
B.水库
C.湖泊
D.渠道
参考答案:A, C
He hurried to the booking office only ____that all the tickets had been sold out . [ ]
A. to tell
B. to be told
C. telling
D. told
若数列{an}对于任意的正整数n满足:an>0且anan+1=n+1,则称数列{an}为“积增数列”。已知“积增数列”{an}中,a1=1,数列{an2+an+12}的前n项和为Sn,则对于任意的正整数n,有[ ]
A、Sn≤2n2+3
B、Sn≥n2+4n
C、Sn≤n2+4n
D、Sn≥n2+3n