Answer:
The third and the fourth option.
![3Mg+1Fe_2O_3 \\ = 3MgO + 2Fe[tex]3Mg+1Fe_2O_3 \\ = 3MgO + 2Fe \\](https://tex.z-dn.net/?f=3Mg%2B1Fe_2O_3%20%5C%5C%20%20%3D%203MgO%20%2B%202Fe%3C%2Fstrong%3E%3C%2Fp%3E%3Cp%3E%3Cstrong%3E%5Btex%5D3Mg%2B1Fe_2O_3%20%5C%5C%20%20%3D%203MgO%20%2B%202Fe%20%5C%5C%20)

Explanation:
The number of products and reactants are balanced
There are thousands of bacterial species and they are not identical towards one another, therefore there forms are quite unique. so its just there characteristics that make up how bacteria look like.
Hope this answers your question.
Background. Plants and animals depend on one another for survival in all of Earth's many habitats. ...
Pollination. Pollination is necessary for plants to create new seeds. ...
Propagation. Another way that animals help plants is by dispersing their seeds to new territory. ...
Fertilization.
Hpe this helps :3
Answer:
The ecosystem will change, maybe, there might be some problems, like some animals will start to die by being food for the alien species, or it might progress more.
Explanation: