Question
Due to human activities, what is the impact on the air
in recent years? 1. The carbon dioxide concentration has increased. 2. Due to various human activities, the air quality in the atmosphere is deteriorating. 3. The temperature of the atmosphere is not rising. Which of the above statements is/are correct?Solution
• Statement 1 is true as carbon dioxide levels have indeed increased in the atmosphere due to human activities such as burning fossil fuels. • Statement 2 is correct because air quality has deteriorated in recent years due to pollution from industrial activities and vehicle emissions. • Statement 3 is incorrect because the temperature of the atmosphere has been rising in recent years, contributing to global warming.
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If the diameter of a sphere is 42 cm, find the total surface area of the sphere.
