保管活水产品的目的在于使之不死或少死，这主要取决于水中的（）。
如果a（－1 to 2），则函数UBound（a）的返回值是（）
A. －1和－2
B. －1
C. －2
D. 2
When accepting vehicles for shipment，the Master should ensure that（）.
A. all decks intended for the stowage of vehicles are，in so far as is practicable，free from oil and grease
B. the ship has on board an adequate supply of cargo securing gear，which is maintained in sound working condition
C. vehicles are in apparent good order and condition suitable for sea transport，particularly with regards to securing
D. All of the above
脱硫剂的作用是脱掉沼气中的硫化氢气体、脱硫剂、再生时可以曝晒。
A. 正确
B. 错误
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