This term refers to over 1200 facilities run by nazi germany during world war ii where the enemies of the nazis were enslaved, starved, tortured and killed.

Concentration camps

Explanation:

    Concentration camp means a military building whose purpose is to detain prisoners of war or political prisoners. Throughout history, there have been several examples of concentration camps that were developed as a way of segregating a given population. Some of the most infamous concentration camps in history are the concentration camps developed by the Nazis over the period between 1933 and 1945.

the underground railroad (apocope of the metropolitan railroad) is a system of urban trains located within a city and its metropolitan area. it is characterized for being a massive transport of passengers in the big cities, uniting diverse zones and their environs, with high capacity and frequency and in segregated form to other systems of transport. metropolitan railroads are built underground or on the surface, although most systems use mixed models where sections are combined in both modalities.

1 - as a result, the metro tends to reduce car travel for two reasons: first, due to the greater transfer of users from the car and, second, due to the reduction in the acquisition of cars in homes located in sectors near the stations of the metro.

2 -the metro allows to contribute effectively to the achievement of all the objectives of an urban development policy: it improves the efficiency of the city's economy by reducing travel costs and also generates a higher level of activities in the city center, taking advantage of of the agglomeration economies.

3 -it is a clean means of transport, since it uses renewable energy (usually electricity), taking care of the environment and avoiding excessive pollution.

b europeans take corn to africa. corn becomes an important crop there.