主要与正气的强弱有关的是（）

A.居住的地域条件

B.工作环境

C.精神状态

D.气候变化

E.以上均非

Before work is commenced（）,the officer responsible should inform the duty en-gineer to ensure that steps are taken to reduce as far as practicable the emission of steam, harmful gases and fumes.

A.near the ship’s whistle

B.on the funnel

C.in the vicinity of radio aerials

D.near the radar scanner