What is the significance of the third estate forming the national assembly and inviting the other estate?

Summoned by King Louis XVI, it was brought to an end when the Third Estate formed into a National Assembly, inviting the other two to join, against the wishes of the King. (This signaled the outbreak of the French Revolution.)

the triple alliance. germany and austria-hungary were already allies by 1879 when, worried about a threat from russia, they formed the dual alliance. italy joined the group in 1882. there was a concern about a possible attack from france and the alliance needed powerful friends to defend it.

i think its 5! hope i