Marco Polo was a Venetian merchant who travelled the Far East reaching the empires of China and Mongolia. Along with his family, interacted with the emperors of both countries and was believed that he was once a special guest of a Chinese emperor during his travels. His voyage made the Europeans know more about the lands at the Far East of the globe and became vital for trade and industry.
Flying Tigers. The 1st American Volunteer Group (AVG) of the Chinese Air Force in 1941–1942, nicknamed the Flying Tigers, was composed of pilots from the United States Army Air Corps (USAAC), Navy (USN), and Marine Corps (USMC), recruited under presidential authority and commanded by Claire Lee Chennault.
The southern colonies (and the colonies in the Caribbeans) required slave labor and indentured servants to maintain plantations that grew valuable crops such as sugar canes and tobacco. Harvesting these crops were often labor intensive that many free workers were unwilling to do without high wages that plantation owners did not wish to pay. These crops could only be grown in the south (or the Caribbean) due to the soil and climate.
Answer: B. Improving Agricultural techniques with Irrigation and fast rising rice increased food supplies.
Explanation:
The Song Dynasty of China which lasted from 960 - 1279 AD saw a great increase in population as well as income. This was due to improvements in Agriculture that led to increased food supplies which could support a larger population.
Some of these improvements included irrigation as more farming commenced on the Yangzi River which increased crop yields as well as the introduction of different types of rice such as fast rising rice which meant that more rice could be grown in planting season.