单项选择题
The（）has a built-in world map; most areas are displayed on a scale of 4000 nm from the top to the bottom of the screen，and can be zoomed in to 150 nm.
A.chartplotter B.C-MAP NT C.C-Cards D.PPI
单项选择题 Radar reflectors are required for（）.
单项选择题 PPI is（）.
单项选择题 Although manual plotting for CPA works well，the workload can become overwhelming when confronted with（）.
