Distinguished guests and friends, welcome to our school, _____ (attend) the ceremony of the 50th Anniversary this morning are our alumni (校友) from home and abroad.
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构成活性污泥的主要微生物是( ),在水处理中起主要作用。( )(本题2.0分)A. 藻类 B. 后生
构成活性污泥的主要微生物是( ),在水处理中起主要作用。( )(本题2.0分)A. 藻类 B. 后生动物 C. 细菌 D. 放线菌