Select all the correct answers. How does the presence of carbon dioxide in the atmosphere help life to flourish on Earth?
by reflecting all solar radiation that falls on Earth
by reflecting UV rays from the Sun back into space
by absorbing an adequate amount of solar radiation
by increasing the thickness of the atmosphere around Earth
by maintaining warm temperatures required for life on Earth

The correct answer is -

3. Butyne

4. Pentene

Explanation:

The names of such organic compounds are classified on the number of the carbon atoms and based on a number these prefixes are attached -

Meth - one carbon

Eth - two carbons

Prop - three carbons

But - four carbons

Pent - five carbons, and so on

The bonds can be identified by names of an organic compound by their suffixes -

- ane = single bond

- ene = double bond

-yne = triple bond

Thus, for question 3, carbon numbers are 4 and triple bond so Butyne, and similarly for question 4, 5 carbon atoms and double bond so Pentene.