Which of the following is NOT a unique characteristic of the current wave of Mexican immigration in the US compared with other waves of immigration.
-The fact that the US a first world country and Mexico a third world country share a un-militarized 2000 mile border
-The fact that the number of immigrants from one country Mexico is multiple times larger than the next several immigrant groups.
-Reginal concentration and is some instances concentration in certain cities.
-Perseistence All the above