What achievement had America achieved over the last 80 years according to President Polk's speech 1845?

Polk accomplished nearly everything that he said he wanted to accomplish as President and everything he had promised in his party's platform: acquisition of the Oregon Territory, California, and the Territory of New Mexico; the positive settlement of the Texas border dispute; lower tariff rates; the establishment of a .. pls mark me branilest

the great wall of china worked as a defense for the feudal states of the zhou dynasty to the north. during the warring states period more walls were put up to defend the borders of the different kingdoms. it was semi successful because despite the wall, the mongols eventually conquered china also the great wall provided protection to the economic development and cultural progress, safeguarded the trading routes such as the silk road, and secured transmission of information and transportation. @jayxboof

1. where does the energy of a nuclear power plant come from?

d) political bosses should not hold office