1._____: The main center-line structural member, running fore and aft along the bottom of a ship, sometimes referred to as the backbone.
A.Frame
B.Deckbeam
C.Stringer
D.Keel
正确答案是D
1._____: The main center-line structural member, running fore and aft along the bottom of a ship, sometimes referred to as the backbone.
A.Frame
B.Deckbeam
C.Stringer
D.Keel
正确答案是D