已知某企业2004-2009年期间工业总产出资料，如下表所示：根据以上材料请回答：该

下列各组物质中，都是强电解质的是(      )

A．HBr、HCI、BaSO₄

B．NH₄Cl、CH₃COOH、Na₂S

C．NaOH、Ca(OH)₂、NH₃·H₂O

D．HClO、NaF、Ba(OH)₂

煤的变质程度越高，其煤尘的爆炸性越强。

发动机的静态参数中，下列哪一个是不能在维护中调节的（）

A.低慢车参数

B.高慢车参数

C.部份功率参数

D.静态起飞功率参数

Which statement concerning the handling characteristics of a fully loaded vessel as compared with those of a light vessel is FALSE?（）

A.A fully loaded vessel will be slower to respond to the engines

B.A fully loaded vessel will maintain her headway further

C.A light vessel will be more affected by the wind

D.A light vessel lose more rudder effect in shallow water

审核完税凭证时就掌握哪些要素？