单项选择题
（）chart 3994，positions read from this chart should be shifted 0.03 minutes Northward．
A.To consider B.To check C.To examine D.To agree with
单项选择题 A Mercator chart is a （）.
单项选择题 A revised print of a chart is made （）.
单项选择题 All straight lines represent great circle tracks on a chart based on a(n) （）.
