单项选择题
A.Wooden (lignum vitae) strips
B.Hard rubber
C.Resin bonded composition
D.Bronze bushings
单项选择题 What best describes the structure from which Stratford Point Light is shown?()
单项选择题 Upon underwater()by divers,there are no apparent()on the bottom plates of the said vessel.
单项选择题 To reduce the number of strakes at the bow,two strakes are tapered and joined at their ends by a single plate. This plate is known as a().