Answer:
The war in the east began with the Russian invasion of East Prussia on 17 August 1914 and the Austro-Hungarian province of Galicia. ... They made some progress, crossing the Carpathians in February and March 1915, but then the German relief helped the Austrians stop further Russian advances.
Explanation:
The answer is, Nations must cooperate to bring about and maintain world peace, and No country must develop or own any sort of nuclear weapons.
In a social system, there are peers and strangers to distract one from pursuing their work. While chatting with others, you may forget your train of thought or a good idea. People are likely to take you away from your work more so than a physical system (in which you can always turn off the TV, but not get people to quiet down)
In order: political cartoon
secondary source
Map
personal narrative
photograph
newspaper editorial
song
