Answer:
Thanks but the answer is true...
After the unification of China in the beginning of the Qin Dynasty, China's First Emperor, Qin Shihuang, linked the walls of the three northern states (Qin, Zhao, and Yan).
Eat Depression<span>, </span><span>worldwide economic downturn that began in 1929 and lasted until about 1939. It was the longest and most severe </span>depression<span> ever experienced by the industrialized Western world, sparking fundamental changes in economic institutions, macroeconomic policy, and economic theory. Although it originated in the </span>United States<span>, the Great Depression caused drastic declines in output, severe </span>unemployment<span>, and </span>acute<span> deflation in almost every country of the world. so it is true</span>
<span>it made trade difficult for merchants whose business crossed state lines.</span>
