单项选择题 （）is a series of trials done at sea to determine whether the ship has met the specifications of design, modification, or repair.

单项选择题 A ship designed for carrying goods requiring refrigeration is called （）.

单项选择题 （）is an opening for supplying seawater to condensers, pumps,etclocated in the hull below the waterline and having means for the attachment of associated piping.