A record of the types and strengths of steels used on a ship must be included in the（）.

A.small plate which fills the aperture between riveted strakes and the vessel framing
B.backing plate which is used to level the strakes while riveting，and then removed
C.internal frame to which the side shell is riveted
D.seam that is welded after riveting is completed

A.When dead in the water，it is often difficult to find the neutral position and slight headway or sternway may result
B.When going directly from full ahead to full astern，there is complete steering control
C.When the vessel has headway and the propeller is in neutral，there is no effect on rudder control
D.When maneuvering in port，full ahead or astern power can usually be obtained without changing shaft RPM