पृथ्वी की सतह से 'ट्रोपोस्फियर' (क्षोभमण्डल) परत की औसत ऊँचाई लगभग कितनी होती है?

The atmospheric phenomenon known as 'Aurora Borealis' occurs in which layer of the atmosphere?

Which of the following represents the correct descending order of gases present in Earth's atmosphere by volume?

Consider the following statements regarding Earth's atmospheric layers: 1. The Troposphere contains almost all weather phenomena. 2. The Stratosphere is mostly free of clouds and contains the ozone layer. 3. The Mesosphere protects Earth by burning up most meteoroids upon entry. Which of the statements given above is/are correct?