🔍 Key Concepts

• Gnomonic vs. Mercator projections – which chart shows great circles as straight lines and rhumb lines as curved lines? • How meridians (lines of longitude) and parallels (lines of latitude) are drawn on different types of projections. • On which chart type is distance normally measured along a meridian at mid‑latitude of the track?

💭 Think About

• First, recall the defining feature of a gnomonic chart: what kind of path shows as a straight line on it? Then think about what happens to all the other lines (meridians, parallels, rhumb lines). • Compare each choice to what you know about a Mercator chart; some options actually describe Mercator properties rather than gnomonic properties. • Ask yourself: on a gnomonic projection, are meridians straight or curved? Are parallels straight or curved? And what happens to a constant‑course (rhumb line) track visually?

✅ Before You Answer

• Be clear on which projection makes great circles appear as straight lines – that’s your anchor fact for gnomonic charts. • Verify which projection uses the rule: “measure distance at the mid‑latitude of the track line” – that belongs to one specific chart type. • Double‑check whether rhumb lines appear straight on gnomonic or on Mercator charts; eliminate any choice that mixes these up.