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.
Answer:
28 million immigrants
Explanation:
Between 1880 and 1930, approximately 28 million immigrants entered the United States. In contrast to earlier waves of immigrants, most of whom had originated in western and northern Europe, this group arrived from eastern and southern Europe.
Think the right answer is b.
Referendum is the political reform that gave people the power to approve or reject laws.
