锅炉的英文()
A、blast furnaDE
B、boiler
C、reboiler
D、bond
参考答案:B
什么叫焊接性?
()of this deratting exemption certificate is hereby extended until 4th 0ct.1988 as the vessel is laden with cargo.
A.Validity
B.Valid
C.Validation
D.The coming into force