21. 以下何種狀況，屬於操縱失靈之船舶“vessel not under command”？
(A) Main Engine breakdown
(B) Vessel loses one of her anchor
(C) launching a rescue boat or a lifeboat
(D) engaged in dredging, surveying or underwater operations

答案：登入後查看
統計： A(1), B(0), C(0), D(0), E(0) #3889500