Trading helped people since it allowed people to not only provide and get things, it also allowed a spread of different innovations/ideas, inventions, and have more cultural diversity. For example, back then when the Colombian exchange happened, many different crops, cattle, etc were brought between the US and Europe. This allowed things that we now have today such as Florida being the main place for the citrus business (citrus came from Europe).
<span>The Song Dynasty developed gunpowder weapons, while the Tang dynasty did not.</span>
Answer:
to retaliate after China's attack on Japanese port cities. I think
