Me asap explain where the carbon stored in fossil fuels comes

The carbon that are stored in the fossil fuels are originated from the dead remains of plants and animals, that were burried millions of year ago, transforming all its carbon content into the newly formed fossil fuel.

        This fossil fuel when used up or burned, will transfer all its energy back into the atmosphere. Almost all the organism contain carbon in their body.

1. efficient use of space

2. elimination of groundwater contamination

3. energy generation

4. lower carbon footprint

cells spend most of their time in interphase