A vessel which is being assisted by an icebreaker should indicate that she is ready to cast off the towline by（）. ["displaying code letter Y (Yankee)","sounding five short blasts on his whistle","displaying code numeral 5","sounding one prolonged blast on his whistle"]
校准的对象是强制性检定之外的计量器具，检定的对象是我国计量法明确规定的强制检定的计量器具。（）
以下哪些设备属于独立太阳能光伏电源系统的主要部件（）。 ["太阳能电池组件","太阳能方阵安装支架","一体化控制器","蓄电池组"]
（）is a function of the reactive / resistive characteristics of the load items and cannot be adjusted by manipulating the alternator control devices. ["Power factor","Power ratio","compression ratio","Compression factor"]
A vessel the passage of which is not to be impeded（）to comply with this Rule when the two vessels are approaching one another so as to involve risk of collision. ["remains fully obliged","has no obligation","is not necessarily","is exempted"]
德嘉线管道主干线材质为（），管径（），设计压力为（）（表压）。
