Acid rain is a form of pollution.
true of false i put true

The correct answer is True.

The acid rain is formed when the humidity of the air is combined with oxides of nitrogen, sulfur dioxide or sulfur trioxide produced by factories, power plants and vehicles that burn coal or petroleum products.

In interaction with the rainwater, these gases form nitric acid, sulfuric acid and sulfuric acid. Finally, these chemicals fall to the ground accompanying the precipitation, and contaminating.

a. because the u.s. was the leading with the most technology, economy, etc. also was teamed with other allies witch boosted the economy and materials to improve technology and use it.

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: