单项选择题
A.40ft B.20ft C.20m D.40m
The safe working load of the derrick is （）.A.5 tonsB.5 ...
单项选择题The safe working load of the derrick is （）.
A.5 tons B.5 metres C.5 feet D.5 mile
Close the （）, please.A. hatch coamingsB. hatch coversC....
单项选择题Close the （）, please.
A. hatch coamings B. hatch covers C. hatch beams D. hatch openings
（）is cargo handling gear.A.DerrickB.CraneC.A+BD.Anchor
单项选择题（）is cargo handling gear.
A.Derrick B.Crane C.A+B D.Anchor
