Arkansas, Colorado,Louisiana,Montana,New Mexico, North Dakota,Oklahoma,South Dakota, Texas, Utah and Wyoming..
Hope that helps
Trench warfare was widely used at the beginning of the war but as it progresses modern military tactics such as infiltration tactics using small groups were used
what do you need to be answered
C) populism
For future reference: an easy way to remember the causes is to use the acronym MAIN (as in the MAIN causes) to remember that they are militarism, alliances, imperialism, and nationalism.
Hope this helps :)