为了保证船舶航行安全，首先要确定船舶的航向与位置。船舶定位方法按照参照目标可分为（　）。

下列哪些证书是《海上交通安全法》要求船舶应具备的（）。
Ⅰ．客船安全证书；Ⅱ．防止油污证书；Ⅲ．船舶执照；Ⅳ．船舶国籍证书。

下列关于船舶安全检查的说法中，正确的是（）。
Ⅰ、船舶接受安全检查时，陪同检查的船员引导检查人员即可
Ⅱ、船舶接受安全检查时，陪同检查的船员应按检查人员要求，调试、操纵有关设备
Ⅲ、中国籍船舶接受安全检查时出示船舶安全检查记录簿

(1) is a method of constructing a project schedule network diagram that uses boxes or rectangles, referred to as nodes, to represent activities and connects them with arrows that show the dependencies.This method includes following types of dependencies or precedence relationships: (2) the initiation of the successor activity, depends upon the completion ofthe predecessor activity.(3) the initiation ofthe successor activity, depends upon the initiation ofthe predecessor activity.

(1) is a method of constructing a project schedule network diagram that uses boxes or rectangles, referred to as nodes, to represent activities and connects them with arrows that show the dependencies.This method includes following types of dependencies or precedence relationships: (2) the initiation of the successor activity, depends upon the completion ofthe predecessor activity.(3) the initiation ofthe successor activity, depends upon the initiation ofthe predecessor activity.

(1) is a method of constructing a project schedule network diagram that uses boxes or rectangles, referred to as nodes, to represent activities and connects them with arrows that show the dependencies.This method includes following types of dependencies or precedence relationships: (2) the initiation of the successor activity, depends upon the completion ofthe predecessor activity.(3) the initiation ofthe successor activity, depends upon the initiation ofthe predecessor activity.