Human Impact Activities Practice Test

A town cleared a large area of forest to build new neighborhoods and roads (urban development). After 2 years, measurements from the same creek downstream showed: average water cloudiness increased from 12 NTU to 48 NTU, and the number of days with muddy runoff after storms increased from 3 days/month to 11 days/month. Impacts can be positive or negative depending on context. Based on this evidence, which statement is supported by the data and shows a clear cause–effect relationship?

A region added many new natural-gas power plants between 2010 and 2020.

Evidence:

• CO₂ emissions: 22 million tons/year (2010) → 31 million tons/year (2020)
• Average number of days with “unhealthy” air quality: 12 days/year → 20 days/year
• Electricity produced: 40 TWh/year → 68 TWh/year

If the same trend in energy use continues for another 10 years without additional controls, what environmental change is most likely based on the evidence? (Impacts can be positive or negative depending on context.)