The helicopter deck of a ship must be marked with the units identification，appropriate aiming circles，and a continuous line on the perimeter which is（）.
A. 8 inches wide
B. 16 inches wide
C. 24 inches wide
D. 32 inches wide
查看答案
部分水解聚丙烯酰的代号是PHP。
A. 正确
B. 错误
材料运输按运输工具的方式有（）种。
A. 4
B. 5
C. 6
D. 7
市场开业前应取得消防安全开业检查合格文件。（）
A. 正确
B. 错误
To prevent loss of stability from free communication flooding you should（）.
A. close the cross-connection valve between the off-center tanks
B. completely flood high center tanks
C. ballast double bottom wing tanks
D. close any opening to the sea in an off-center tank
微信支付 
支付宝支付