The Triple Entente WAS NOT an alliance - nothing was ever signed by Britain.It was an understanding in the early 20th century between Britain,France,and Russia by which they all agreed that none of them liked Germany much,and effectively admitted that they all therefore had a common interest in opposing German aims.
The Triple Alliance was a full alliance between Germany,Austria-Hungary,and Italy signed in 1882,the purpose of which was to keep France isolated.When WW1 began in 1914,Italy welshed on the alliance on the grounds that the war was caused by German aggression (a popular international view long before the Treaty of Versailles).
Yes it is its not allowed to trade with other countries
To encourage an ethnically diverse population, Germany wanted control on who should be who.
Leads to competition,antagonism between nations
