Qustions on Small Sheet

1. What had to happen for complex multi-cellular life to take hold was that the Earth atmosphere had to have oxygen. Oxygen come to the Earth because of small photosynthetic plant. The plants breathed in the Co2 in the air and exhaled out oxygen. Oxygen would be able to new life the ability to breath in clean air and stay alive and would develop up new life forms.

2. The Archaean Eon was the significant in terms of development of the Earth because this was the eon when the Earth was born. This was the beginning of everything that was going to happen to the Earth. That's why it is the most significant eon in terms of the Earth development.

3. This significant of the humans presence on the Earth is pretty big because humans have change the Earth in many ways. Humans have poluted the Earth with oil and gas which are change into CO2 when humans drive cars. Humans have has made nuclear bomb that make area on the Earth unhatabitl for humans, animals, and plants. Humans have also helped the Earth by plating trees, recycling, and making thing that helps the enviroment like wind turbines.