Which projection requires a separate computation and map for each city or base on which the map is centered?

• A. Azimuthal equidistant
• B. Orthographic
• C. Lambert conformal conic
• D. Mercator

Answer: (A)

Centering a map in an azimuthal projection uses a plane tangent at a single center and preserves true distances from that center to all other points. Because the whole layout is built around that chosen center, changing the center to a different city means recomputing all coordinates from the sphere to the plane and creating a new map. The projection is defined specifically by that center, so you can’t have one map that preserves distances from multiple centers simultaneously. The other projections are not tied to a single center in the same way, so they don’t require separate maps for each possible center in the same sense.