Which event caused southern states to secede from the union, just weeks after it happened?

a. the institution of stronger tariffs
b. the election of abraham lincoln
c. john brown's raid on harper's ferry
d. the publication of uncle tom's cabin

the hyksos invasion. the hyksos were able to attack egypt successfully because of their skills in using bronze weapons, composite bows and the use of the horse and chariot during the invasion. although the egyptians depict a barbarian-type overthrow, the truth is the seizure was likely a relatively peaceful one.

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.