C, a little depressed. Brooding is close to showing deep unhappiness of thought.
Answer:
The 15 "Sunbelt" states are: Alabama, Arizona, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, Nevada, New Mexico, North Carolina, Oklahoma, South Carolina, Tennessee, and Texas.
Explanation:
People would be interested in moving to them because the climate is warm and sunny. And around the 1960s there were many growing economic opportunities.
Math is the area where we struggle in the most.
I would say trading cities became more important