Assess students' ability to recall common environmental tracers and isotopic systems used in paleoenvironmental reconstruction—e.g., stable isotopes (δ18O, δ13C, δ2H, δ15N), radiocarbon and cosmogenic isotopes (14C, 10Be), biomarkers, trace metals, pollen, and microfossil assemblages—identify their physical/chemical basis, typical archives (ice cores, speleothems, marine/lake sediments, corals), primary applications (temperature, precipitation/source water, trophic status, age control, erosion, ocean circulation), and typical timescales/resolution.