It's the first one where it resist change in pH solutions by neutralizing :)
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Global warming
Extra carbon dioxide in the atmosphere will increases the greenhouse effect. More thermal energy is trapped by the atmosphere, causing the planet to become warmer than it would be naturally. That increases the Earth's temperature which is also called Global Warming
200,000 is the population density.
Answer:
Scientists have identified a key difference in the way our immune systems respond to viral and bacterial pathogens. ... These hormone-like molecules control communication between cells to trigger defensive action by the body's immune system when pathogens such as bacteria, viruses, or parasites are detected.
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