Based on the chart and your knowledge of this period in american history, it can be concluded that federal spending between the years of 1936 and 1938.

The correct answer to this open question is the following.

Federal Spending between the years of 1936 and 1938 declined due to the improved of the economy.

After the United States stock market crash of October 29, 1929, it represented the beginning of the Great Depression that hurt so much the economy of the country and left millions of Americans without jobs. When President Franklin D. Roosevelt created a series of programs called "New Deal." The Federal Government increased the expenditure to create social programs to help the people in need. After things began to recover and people started to improve their condition, the Federal Spending between the years of 1936 and 1938 declined due to the improved of the economy.

a. theta waves. this is because the person is in a light sleep which means the brain waves would show these kind of waves.