Uncertainty and units Scope Use this skill whenever a calculation carries physical units or a reported number needs an uncertainty. Concretely: - converting between units, including conversions that need a physical context (wavelength to photon energy, mass to amount of substance, energy to temperature); - propagating uncertainty through a measurement model, with or without correlated inputs; - building a GUM uncertainty budget from calibration certificates, specifications, and repeatability data; - choosing a coverage factor and deciding whether is defensible; - rounding and writing a result…