Question : In which of the following layers of the atmosphere do the absorption and scattering of solar ultraviolet radiation take place?

Option 1: Troposphere

Option 2: Stratosphere

Option 3: Mesosphere

Option 4: Thermosphere

Question : Which of the following helps keep the Earth's atmosphere in place?

Option 1: The gravitational force of the moon

Option 2: Rotation of the Earth on its axis

Option 3: The gravitational force of the Earth

Option 4: The gravitational force of the Sun

Question : Which is the most abundant mineral in the Earth's continental crust?

Option 1: Pyroxenes

Option 2: Quartz

Option 3: Feldspar

Option 4: Mica

Question : The Earth's perihelion occurs in:

Option 1: July

Option 2: October

Option 3: January

Option 4: September

Question : Living organisms have been on Earth for how much per cent of Earth's history?

Option 1: 80%

Option 2: 20%

Option 3: 60%

Option 4: 40%