How did the United States military (AEF) impact the outcome of
WWI?

The impact of the United States joining the war was significant. The additional firepower, resources, and soldiers of the U.S. helped to tip the balance of the war in favor of the Allies.

Explanation:

the number of calories in each pack of cookies has a greater variation than the number of calories in each pack of crackers.

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: