Matter in an ecosystem flows only one way is part of an open system is eventually lost as heat is broken down into chemical nutrients

option d is correct. corroborated sources of historical evidence   is necessary to validate a claim about an event in history.

historians tend to use written sources, but audio and visual materials as well as artifacts are important objects that supply information to modern historians.

historical sources are usually divided into two categories: primary and secondary sources. depending on the historian's intent, some sources shift their designation. determining what type of sources toimplement, and the level of credibility and reliability of those sources, is a significant step in critical thinking for the historian.

explanation:

our current president donald trump

1 problem today is that it caused to much crime americans are born with freedom and liberty and not being restricted to things causing lots of crimes because there free until proven guilty and commit a crime

the pursuit of order has only made people hate order causing race profiling and   more

3 it has to much liberty the liberty is to much because it causes to much crime and aswell hacking and letting hackers open to numerous things such as stealing cards and more