What are the differences between primary and secondary sources?

"a shortage of traditional labor created new opportunities in the workplace. a major cause of the internment of japanese americans during world war ii was. racial prejudice. in the early 1940's, the "destroyers-for-military-bases deal" with great britain and the lend-lease act were evidence that the united states."

spanish executed counts egmont and horne in brussels.

copernicus finished the first manuscript of his book, "de revolutionibus orbium coelestium" ("on the revolutions of the heavenly spheres") in 1532. in it, copernicus established that the planets orbited the sun rather than the earth. he laid out his model of the solar system and the path of the planets.