問題詳情
27. ____________ tells navigators how deep the sea depth is by sending signals from thebottom of the ship hull to the sea bed.
(A) Echo sounder
(B) Automatic Identification System
(C) Global Positioning System
(D) Navtex
參考答案
答案：A
難度：非常簡單0.85
書單：沒有書單，新增