Geographic Data Practice Test

A city planning office compiles a 2019 report (75–125 words) using secondary sources: national census tables, a state health department database, and a university study. The report notes that census counts can underrepresent undocumented residents and unhoused populations, and that neighborhood boundaries used in different datasets do not match. The planners want to map “service gaps” for clinics by neighborhood. Which statement best reflects a key limitation and potential bias when using these secondary geographic datasets together?

A 95-word secondary-source description explains how GIS and spatial databases store features as points, lines, and polygons with attributes, and warns that results depend on how layers are created (classification, scale, and projection). A county overlays a flood-risk polygon layer with parcel polygons to estimate how many homes are at risk, but the flood layer was created at a much coarser scale than the parcel data. What is the most accurate concern?