What event caused the United States to enter World War I? A) Unrestricted submarine warfare
B) The zimmerman telegram
C) The sinking of the Luisitania
D) Germany's invasion of Poland

the answers are 1 and 4

ww1 weapons: tank. tanks were used for the first time in the first world war at the battle of the somme. they were developed to cope with the conditions on the western front. the first tank was called 'little willie' and needed a crew of 3.

there are hundreds of postives ways to unite a country with another country here are a   few

1 peace treaty's peace treatys

are basically a document signing a allliance with one country and another.

2 gift

what i mean by this is for example how the french gave the americans the statue of libery a gift of peace.