5 Yrs as a legal resident.
3 months.
As long as said person has a citizenship in Mexico, they should be able to stay for as long as they want. However, it may be wise to get an identification card, but it shouldn't be needed.
For 30 years, granted you have the Mexican citizenship.
8 years
5 year u can apply for citizenship its dep. if u r legally enter in us
Generally, as long as you want. Some counties (UK for example) allow citizenship to be revoked by the government unilaterally (i.e. they think you're a terrorist, and you have citizenship in another country. Cannot lose U.S. citizenship unless you revoke it, in person, outside the U.S. at an embassy.
How long does he take to get your citizenship for australia?
A friend request will stay pending on Facebook until the person accepts or denies the request. This could mean years if the person simply refuses to respond.
I do not know How long they live
If you are an Italian citizen you can live in Italy whenever you like as long as you like, regardless of your other citizenships.
US and UK allow Dual citizenship. A person can be a US citizen and a citizen of UK if he/she desires to. But if a person applies to get naturalized as a citizen of UK when he/she is already a US citizen, then it will lead to losing US citizenship.So a person can have US & UK citizenship as long he/she is not a naturalized citizen of UK.
You do not have to live in Vegas to get married there. As long as you both have proof of citizenship you can get married at pretty much any chapel in town.