单项选择题
Entering from sea，a daymark on the port side of the channel would be indicated on a chart by a （）.
A.red triangle with the letter R B.white triangle with the letters RG C.green square with the letter G D.white square with the letters GR
单项选择题 Distance along a track line is measured on a Mercator chart by using the （）.
单项选择题 Attention is （）the advice on the use of charts in The Mariner’s Handbook Chapter 3，Section 1.
单项选择题 Admiralty Charts are published in （）.
