Beacuse if we all did what we were supposed to do and worked hard we would have basicaly a perfect country. This helps us out with our economy for example
The Columbian Exchange also had positive and negative effects. The positive side was the exchange of technology in agriculture, for example, which increased crop yields and food production in favor of Native Americans and in favor of Europeans. One of the negative effects was certainly the appearance of many diseases that Europeans transferred to the American continent. Native Americans first faced such illnesses, were non-resistant to them, and many of them died.
The correct answer according to the options offered is: A.
The Tang Materia Medica was the first <em>pharmaceutical</em> book.
Materia Medica is the Latin term for collected knowledge about healing substances. The Tang Materia medica was written circa 659 CE and it is one of many contributions by the Tang dynasty to science. The book, published by the then ruling Chinese government, is a compilation of drugs and instructions for their use. The book has 54 volumes, divided into 3 parts:
- The Main body (20 volumes) and Table of contents (1 volume).
- Pictures of medicines (25 volumes) and Table of contents (1 volume).
- Illustrated description (7 volumes).
After it was published and distributed throughout the country by the Tang government, it became the national basis for the medical practice for more than 400 years.
I think you should double check it and see if you can find the answer if not come back and ask again