To date rocks, scientists use
O U238
C14
O K-Pg
O Iridium

Yes he is right they are bacteria

Answer is b)eutrophication occurs when excess nutrients are present in aquatic ecosystems, resulting in the increased production of plant life and the subsequent decrease in the oxygen levels of the watereutrophication occurs when there are excess nutrients in a body of water. this results in plants having more food and reproducing  more, sometimes leading to more aquatic animal life as well. ultimately, this can reduce the oxygen level in the ecosystem. 

1.  culture plays a role in boundary disputes.
2.  female children are encouraged to marry at a young age.
3.  forests are cleared to provide housing.
4.  settlement patterns are influenced by culture.
5.  spanish is spoken in parts of texas.