問題詳情

12. Generalemergency alarm means a sound signal of seven short blasts and one _____  blastgiven with the vessel’s sound system.
(A). big
(B). short
(C). enforce
(D). prolonged 

參考答案

答案：D
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)