Can someone please help me with this.

3) 1/4

4) dawn to dark (it's from dawn to dark if it's "dawn to dark, from")

24.9% of people were unemployed

Explanation:

"Employment dropped by 20.5 million, more than 10 times the previous largest monthly decrease of 1.96 million experienced in September 1945 after World War II ended. At that point in time this was about 3.3% of the workforce."

c, they united with once