航海英語海圖及海圖作業(yè)單項選擇題每日一練(2019.05.04)

來源：考試資料網(wǎng)

1 Which aid is NOT marked on a chart with a magenta circle? （）

2 Lines on a chart which connect points of equal magnetic variation are called （）.

3 When a buoy is in position only during a certain period of the year，where may the dates when the buoy is in position be found?（）

4 （）is not a position-fixing system.

5 Which information does the outer ring of a compass rose on a nautical chart provide（）.