Answer:
Life began on Earth at least 3.5 to 4 billion years ago, and it has been evolving ever since. At first, all living things on Earth were simple, single-celled organisms. Much later, the first multicellular organisms evolved, and after that, Earth's biodiversity greatly increased.
Explanation:
Answer:
1.to protect people to any virus and to look attractive
2. to maitain a good system and good condition
3.on the cleaniest place and have good air
Answer: A medium-mass star will become a white dwarf at the end of it's life cycle.
Explanation:
The life cycle of a medium-mass star (according to the picture, which I can attach for you if you want) is:
1. Interstellar Cloud
2. Protostar
3. Small Star
4. Red Giant
5. Planetary Nebula
6. White Dwarf