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OpenStem
@openstem · Joined Jul 2026
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Quiz5 questions
What does the 'R' in CLORPT stand for?
ARainfallBRelief (topography)CRock typeDRoot density
Environmental · L4 · Soil Science (Pedology) — 5 Q
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Environmental · L4 · Soil Science (Pedology) — 5 QQuiz5 questions
In the water balance equation P = ET + Q + ΔS, what does ΔS represent?
ATotal streamflow leaving the watershedBThe change in water storage (soil moisture, groundwater, surface water)CSolar radiation reaching the watershedDThe runoff coefficient
Environmental · L4 · Quantitative Hydrology — 5 Q
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Environmental · L4 · Quantitative Hydrology — 5 QQuiz5 questions
Without VOCs present, why doesn't the basic NO2 photolysis cycle cause ozone to build up indefinitely?
ANO2 does not absorb sunlightBThe ozone produced reacts back with NO, regenerating NO2 in a closed null cycleCOzone is destroyed by rain immediatelyDNO2 only forms at night
Environmental · L4 · Atmospheric Chemistry — 5 Q
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Environmental · L4 · Atmospheric Chemistry — 5 QQuiz5 questions
What does a LOWER LD50 value indicate about a substance?
AThe substance is less toxicBThe substance is more toxicCThe substance has no lethal doseDLD50 does not relate to toxicity
Environmental · L4 · Environmental Toxicology — 5 Q
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Environmental · L4 · Environmental Toxicology — 5 QQuiz5 questions
In the NDVI formula (NIR - Red)/(NIR + Red), why does healthy vegetation give a HIGH value?
AHealthy leaves absorb NIR and reflect red stronglyBHealthy leaves reflect NIR strongly (leaf structure) while absorbing red strongly (chlorophyll for photosynthesis)CNDVI has nothing to do with reflectanceDHealthy leaves reflect both NIR and red equally
Environmental · L4 · Remote Sensing & GIS — 5 Q
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Environmental · L4 · Remote Sensing & GIS — 5 QQuiz5 questions
What does NEPA fundamentally require of U.S. federal agencies?
AThat they cannot approve any project with any environmental impactBThat they assess and disclose the environmental effects of major actions before deciding, and consider alternativesCThat they set air quality standardsDThat they issue NPDES permits
Environmental · L4 · Environmental Law & Regulation — 5 Q
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Environmental · L4 · Environmental Law & Regulation — 5 QQuiz5 questions
What basic principle does material flow analysis (MFA) apply to a system like a factory or a city?
ASupply and demand pricingBMass balance: Inputs = Outputs + AccumulationCCarbon datingDLife-cycle discount rates
Environmental · L4 · Industrial Ecology — 5 Q
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Environmental · L4 · Industrial Ecology — 5 QQuiz5 questions
What two conditions does the Coase theorem require for private bargaining to reach an efficient outcome?
AHigh transaction costs and undefined property rightsBWell-defined property rights and low transaction costsCGovernment price controls and subsidiesDA single monopoly firm and no competition
Environmental · L4 · Environmental Economics — 5 Q
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Environmental · L4 · Environmental Economics — 5 QQuiz5 questions
According to SER, what is the critical additional requirement for a site to count as 'restored', beyond just having the right species present?
AIt must be fenced off from all human accessBIt must function self-sustainingly, with normal ecological processes and resilience, needing minimal ongoing interventionCIt must be larger than the original degraded siteDIt must contain no non-native species whatsoever
Environmental · L4 · Restoration Ecology — 5 Q
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Environmental · L4 · Restoration Ecology — 5 QQuiz5 questions
Which treatment stage uses biological processes (like activated sludge) to remove dissolved organic matter?
APrimary treatmentBSecondary treatmentCScreeningDDisinfection
Environmental · L4 · Wastewater Treatment Engineering — 5 Q
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Environmental · L4 · Wastewater Treatment Engineering — 5 QQuiz5 questions
What is the removal mechanism of an electrostatic precipitator (ESP)?
APhysically straining gas through fabric bagsBCharging particles electrically and collecting them on oppositely charged platesCDissolving particles in a limestone slurryDCatalytic oxidation
Environmental · L4 · Air Pollution Control Engineering — 5 Q
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Environmental · L4 · Air Pollution Control Engineering — 5 QQuiz5 questions
What does a General Circulation Model (GCM) numerically solve?
AOnly historical temperature recordsBThe physical equations of fluid motion, radiation, and thermodynamics on a 3D gridCOnly economic growth projectionsDA single-column atmosphere with no ocean or land coupling
Environmental · L4 · Climate Modeling — 5 Q
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Environmental · L4 · Climate Modeling — 5 QQuiz6 questions
Minimum Viable Population (MVP) is best described as:
AA fixed number that applies identically across all speciesBThe smallest population size projected to have a chosen probability of persisting over a chosen time horizonCThe current census count of a speciesDThe carrying capacity of a habitat
Environmental · L4 · Conservation Biology & Population Viability — 6 Q
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Environmental · L4 · Conservation Biology & Population Viability — 6 QQuiz6 questions
Two identical 65 dB machines run simultaneously. What is the approximate combined sound level?
A68 dBB95 dBC130 dBD65 dB, unchanged
Environmental · L4 · Environmental Acoustics & Noise Pollution — 6 Q
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Environmental · L4 · Environmental Acoustics & Noise Pollution — 6 QQuiz6 questions
Which of the four risk assessment steps determines how much of a chemical people actually contact and via what pathway?
AHazard identificationBDose-response assessmentCExposure assessmentDRisk characterization
Environmental · L4 · Human Health Risk Assessment — 6 Q
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Environmental · L4 · Human Health Risk Assessment — 6 QQuiz6 questions
Which of the following is NOT one of IWRM's three commonly cited pillars?
AEconomic efficiencyBSocial equityCEnvironmental sustainabilityDMaximum short-term extraction
Environmental · L4 · Integrated Water Resources Management — 6 Q
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Environmental · L4 · Integrated Water Resources Management — 6 QQuiz6 questions
A 50 MW solar farm produces 100,000 MWh over a year (8,760 hours). What is its capacity factor?
A~11%B~23%C~46%D~91%
Environmental · L4 · Renewable Energy Systems Engineering — 6 Q
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Environmental · L4 · Renewable Energy Systems Engineering — 6 QQuiz6 questions
What is the primary purpose of a composite liner beneath a sanitary landfill?
ATo improve the aesthetics of the siteBTo prevent leachate from percolating into underlying soil and groundwaterCTo increase landfill gas generationDTo reduce daily cover requirements
Environmental · L4 · Solid Waste Management Engineering — 6 Q
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Environmental · L4 · Solid Waste Management Engineering — 6 QQuiz6 questions
What does the 'screening' step of an EIA decide?
AWhich specific impacts the study will investigateBWhether the proposed project requires a full EIA at allCThe final approval decision for the projectDHow much offset is owed for residual impact
Environmental · L4 · Environmental Impact Assessment — 6 Q
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Environmental · L4 · Environmental Impact Assessment — 6 QQuiz4 questions
The radiative forcing due to a doubling of CO₂ is well-approximated by the IPCC formula ΔF = 5.35 ln(C/C₀). What is the forcing for a CO₂ doubling (C/C₀ = 2)?
AApproximately 1.5 W/m²BApproximately 3.7 W/m²CApproximately 7.4 W/m²DApproximately 10.7 W/m²
Environmental · L5 · Ocean Acidification, Radiative Forcing, and Plate Geodesy
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Environmental · L5 · Ocean Acidification, Radiative Forcing, and Plate GeodesyQuiz4 questions
The Rossby number is defined as Ro = U/(fL). What does a small Rossby number (Ro ≪ 1) imply about the flow?
ACoriolis forces dominate; geostrophic balance is a good approximation.BInertial forces dominate; the flow is ageostrophic.CViscous forces dominate; the flow is laminar.DThe flow is supersonic and compressible.
Environmental · L5 · Geophysical Fluid Dynamics
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Environmental · L5 · Geophysical Fluid DynamicsQuiz5 questions
The steady-state condition for a multi-box model requires:
AEvery pairwise flux F_ij equals its reverse F_jiBdM_i/dt = 0 for every reservoir — total inflow balances total outflow per boxCAll reservoirs hold equal massDAll rate constants k_i are equal
Environmental · L5 · Quantitative Biogeochemical Cycle Modeling
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Environmental · L5 · Quantitative Biogeochemical Cycle ModelingQuiz5 questions
A δ¹⁸O value is reported relative to what?
AThe absolute concentration of ¹⁸O in the sampleBAn international isotope-ratio standard (e.g. VSMOW or VPDB), in per mil deviationCThe sample's own average over its entire depthDThe modern atmospheric CO₂ concentration
Environmental · L5 · Paleoclimate Proxies & Isotope Geochemistry
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Environmental · L5 · Paleoclimate Proxies & Isotope GeochemistryQuiz5 questions
The Beer–Lambert law I(τ) = I₀e^(−τ) describes:
ALinear attenuation of intensity with optical depthBExponential attenuation of intensity with optical depthCIntensity increasing with optical depthDA relation that only applies to visible light
Environmental · L5 · Atmospheric Radiative Transfer
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Environmental · L5 · Atmospheric Radiative TransferQuiz5 questions
In the Levins model dp/dt = cp(1−p) − ep, what does p represent?
AThe total population abundance across all patchesBThe fraction of habitat patches currently occupiedCThe probability of extinction for a single individualDThe dispersal distance between patches
Environmental · L5 · Landscape Ecology & Metapopulation Dynamics
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Environmental · L5 · Landscape Ecology & Metapopulation DynamicsQuiz5 questions
Why does ignoring autocorrelation when significance-testing a climate trend tend to overstate confidence?
AAutocorrelation always increases the true trend magnitudeBStandard tests assume independent observations; correlated data carry fewer truly independent data points than the raw sample size suggests, so uncorrected standard errors are too smallCAutocorrelated data cannot be plottedDIt has no effect — significance tests are unaffected by correlation structure
Environmental · L5 · Environmental Statistics: Trend Detection
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Environmental · L5 · Environmental Statistics: Trend DetectionQuiz5 questions
In ΔN = ΔF − λΔT, what does a SMALLER (weaker) net λ imply about equilibrium warming for a given forcing ΔF?
ALess warming, since λ is inversely related to sensitivityBMORE warming — ΔT_eq = ΔF/λ grows as λ shrinksCNo change — λ does not affect equilibrium temperatureDThe forcing itself must decrease
Environmental · L5 · Earth System Feedback Quantification
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Environmental · L5 · Earth System Feedback QuantificationQuiz5 questions
In the Richards equation, what makes it numerically much harder to solve than saturated (fully Darcy) groundwater flow?
AIt has no time derivativeBK(θ) and ψ(θ) are strongly nonlinear functions of water content, requiring iterative numerical solution methodsCIt only applies to frozen soilsDIt has no spatial derivatives
Environmental · L5 · Hydrological Modeling
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Environmental · L5 · Hydrological ModelingQuiz5 questions
What does the probit transform assume about the distribution of individual organism tolerances?
ATolerances are log-normally distributed across the populationBAll individuals have identical toleranceCTolerances follow a uniform distributionDTolerance has no relationship to dose
Environmental · L5 · Quantitative Ecotoxicology
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Environmental · L5 · Quantitative EcotoxicologyQuiz5 questions
Why does raw top-of-atmosphere (TOA) radiance need correction before quantitative land-surface analysis?
ATOA radiance already equals true surface reflectanceBAtmospheric scattering and absorption distort the surface signal wavelength-dependently on both the down- and up-pathCSatellites cannot measure radiance at allDSurface reflectance has no wavelength dependence
Environmental · L5 · Remote Sensing Retrieval & Inversion Algorithms
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Environmental · L5 · Remote Sensing Retrieval & Inversion Algorithms