no
Yes, as there are some restrictions on what can you bring back. For instance, you can bring two laptops without paying any further taxes; if you bring a third laptop you have to declare it before "hacienda" and pay the appropriate tax.
It depends on the import restrictions of the country to which you are returning.
There are no laws for such things, but I don't think the power currents would be compatible, the US is NTSC format and Europe is PAL
The only thing that Columbus offered to the king and queen of Spain was a promise to bring back riches. He did not give them any tangible thing.
You are able to bring 60 packets of 50g back from Spain.
In Spain the minimum age is 16. There are no age restrictions in Mexico.
to start a colony that would bring profits to Spain
The gradual removal of trade restrictions
There are no such restrictions in Mexico, which is a country where a majority of its population practices Roman Catholicism. Other countries with such religion are Portugal, Spain, France or Italy, and neither of them has any import/export restrictions due to religious beliefs.
No.
You can bring back 2 tax free quarts of distilled alcohol from any country.
No. ask the Chinese under Chairman Mao.