单项选择题
A.be safe if mixed with fresh water B.prevent seasickness C.dehydrate you D.protect against heat cramps
Chemical burns are caused by the skin coming in contact...
单项选择题Chemical burns are caused by the skin coming in contact with（）.
A.acids or alkalies B.diesel oil C.acids，but not alkalies D.alkalies，but not acids
Changing rescuers while carrying out artificial respira...
单项选择题Changing rescuers while carrying out artificial respiration should be done（）.
A.without losing the rhythm of respiration B.only with the help of two other people C.by not stopping the respiration for more than 5 minutes D.at ten-minute intervals
Before personnel are lifted from a vessel in a personne...
单项选择题Before personnel are lifted from a vessel in a personnel basket，the vessel should be（）.
A.directly under the boom B.moving away from the boom C.stopped dead in the water D.tied to the boom
