Why was the iron curtain a problem?

it prevented the allies from knowing what the soviets were up to.

the soviets were participating in the cold war.

it blockaded access to berlin.

it separated north and south korea.

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:

during the 20th century, the role of the vice president has evolved into more of an executive branch position. now, the vice president is usually seen as an integral part of a president's administration and presides over the senate only on ceremonial occasions or when a tie-breaking vote may be needed.

1. explain aspects of the democratic process as it was developed in ancient athens

2. trace the roots of the americans political process to ancient athens

3. explain the relationship of citizens to the political process

the citation´s place is in position 4.

as carl becker

pointed out during the rise of european fascism after world war i

for democracy to prosper, it needs “a certain measure of economic security”

.

example (johnson 4)