航海英語燃燒與爆炸單項(xiàng)選擇題每日一練(2019.01.23)

來源：考試資料網(wǎng)

1 Each fire hose coupling on a ship must have threads that meet the specifications of the（）.

2 Each hand portable fire extinguisher must be marked with（）.

3 A carbon dioxide fire extinguisher should be recharged（）.

4 A cutoff valve in the fire-main system of a ship may be closed to protect the portion of the system on an exposed deck from（）.

5 On a hydrocarbon flammability chart the line which extends from 0% to 21.8% oxygen，lying tangent to the flammability range，is called the（）.