Under a time charter party ， the charterer pays for（）.
A. capital cost
B. fuel
C. ling costs
D. wages of crew
The Air Waybill serves as（）.
A. a document of title to the s
B. a contract for transporion
C. a receipt and delivery of shipment
D. a convention for air transport
稳定阶段主要是指转移到活性污泥上的有机物为微生物所利用（）
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