For Copernicus, I think it was On the Revolution of the Celestial Spheres. I think For Newton it was Philosophiæ Naturalis Principia Mathematica.
To support their claim would be my guess
dual court system the division of the courts into two separate systems, one federal and one state, with each of the fifty states having its own courts. trial court the level of court in which a case starts or is first tried.
Answer:
Explanation: 1) Stalin became the dictator of the USSR.-late 1920's
2) Khrushchev became the general Secretary - September 1953
3) De-Stalinization began- 1953 after Khrushchev achieved power
3) Sputnik was launched- May 1957
4 Yuri Gagarin became the first man in space-April 12, 1961
One important advantage that primary soruces have over secondary sources is that primary sources offer a firsthand account of an event - b, which isn't the case with secondary sources. Although this leaves primary sources prone to being biased compared to secondary sources.
