Ozone Layer is depleting: Air pollution
Aluminium composition on Earth: 1.59%
The sun derives its energy from: Nuclear fusion reactions
Earth is : Perfect sphere
Geology describes the rocky parts of the Earth's: Crust
In general, Comets have ______ orbits: Elliptical
The season changes because of the _______? Earth is revolving around the sun
These are cooler areas which move about on the sun's surface and show up as dark spots: Sun-spots
What is the rank of the earth in the solar system in terms of size? Fifth
The earth revolves around the sun at a speed of: 29 km/sec
