单项选择题
A.engaged in the coastwise trade B.going foreign C.calling at ports in another country signatory to MARPOL 73/78 D.carrying cargoes listed in the MARPOL regulations
Before welding can be done in a tank that has carried p...
单项选择题Before welding can be done in a tank that has carried petroleum products，a certificate must be obtained from（）.
A.the Customs B.the Register Bureau of Shipping C.the Shipyard Fire Department D.a certified gas chemist
