How is modern Earth different from Earth over four billion years ago?

Constantly bombarded with comets and asteroids
Little to no oxygen
High levels of ultraviolet radiation
Protective atmosphere

Respuesta :

Answer: little to no oxygen

Explanation:

Early earth had low oxygen, UV radiation, high heat, not a lot of water. Modern earth has lots of oxygen, low UV radiation, abundant amount of water, ozone layer.

ACCESS MORE