Question
Which gas is the main contributor to the greenhouse effect?
▶️Answer/Explanation
Question
The graph shows atmospheric oxygen levels over time.
About 2.5 billion years ago, a significant rise in atmospheric oxygen occurred. What was the cause of this rise?
A. Photosynthesis by non-vascular land plants
B. Photosynthesis by vascular land plants
C. Oxygen produced by photosynthetic bacteria being released from the ocean into the atmosphere
D. Volcanic activity
▶️Answer/Explanation
Ans:C
Question
Deforestation and agricultural activities including the production of crops and livestock are thought to play a major role in the greenhouse effect. The graph shows annual trends in rates of deforestation and the production of soybeans and cattle in the state of Mato Grosso in Brazil in the period from 2001 to 2010.
What conclusion can be drawn from the information in this graph?
A. The decline in rates of deforestation led to an increase in production of CO2.
B. Soybean production accounted for a greater proportion of deforestation than cattle production.
C. Forest habitats declined during the first few years of the study.
D. The decline in rates of deforestation is due to an increase in soybean production.
▶️Answer/Explanation
Ans:C