以下选项中，不属于多媒体计算机应用软件的是（）。 多媒体教学课件。 多媒体模拟系统。 多媒体演示系统。 多媒体编辑与创作工具。
简述斜管虫病的病源。
乘积型相位鉴频器由（）、（）和（）等组成。
A vessel is equipped with cross-connected deep tanks. In which situation should the cross-connection valve be closed? （） The tanks lie above the waterline and are filled。 The tanks are partially filled with dry cargo。 The tanks are partially filled with liquid cargo。 The tanks are filled and lie below the waterline。
When a vacuum boiling evaporator works, the hot jacket water will pass over the tube stack and （） the sea water passing through the tubes. dispose。 dissolve。 heat。 dissipate。
With a vacuum boiling evaporator, the remainder of sea water fed to the evaporator is pumped out by （）.
