急性心肌梗死表现为（）

A.咳喘，呼吸困难伴发热

B.颈静脉怒张，肝肿大，下肢水肿

C.突然剧烈胸痛，呼吸频促伴呼吸困难，紫绀，心电图P波高尖

D.胸痛，大汗伴呼吸困难，心电图ST段抬高

E.颈静脉怒张，肝肿大，奇脉，活动时气短

To improve your vessel’s stabilty in a hazardous situation, you should（）.

A.ballast deep tanks if they are slack

B.transfer ballast athwarships

C.pump out double bottoms

D.fill double bottom from deep tanks