A historian is researching daily life in Ancient Egypt under a variety of ruling families over hundreds of years. This historian is using which of the following ways to study the past?
cause and effect
changes over time
sequence of events
similarities and differences

the answer to your question is:

strong-mayor system

study of past cultures

c. free trade can lead to low pay for workers in poorer countries.

the emancipation proclamation was the aim of the war change to include the freeing of slaves in addition to preserving the union. the 13th amendment, which abolished slavery in the u.s. was passed on december 6th 1865.

as promised, lincoln waited to unveil the proclamation until he could do so with success from the union military advance. on september 22nd 1862, after a victory at antietam, he publicly announced a preliminary emancipation proclamation, declaring all slaves free in the rebellious states as of january 1st 1863.