What challenges were experienced by black folks in America in the decades leading up To the civil rights movement?

the american rail road was the most influential and useful transportation system developed in the 1800's with steam locomotives and in the very late 1800's and early 1900's diesel electric locomotives being used to transport goods and people around the newly expanded united states!

that’s true, tatiana prouskouriakoff established that the inscriptions were primarily historical.   they recorded events in the lives of mayan rulers and their families.

the answer wold be b) travel among nations should be regulated by an international organization

. political or economical policy that isolates a country from participating in international relationships. it has been suggested that the united states participates in isolationism because of its lack of involvement in particular wars or alliances.