阅读下列材料：
材料一：读图

材料二：公元前一世纪，欧洲罗马共和国执政官凯撒，曾穿着丝袍出现在剧场，轰动一时。到后来，穿着中国锦衣绣服，成为罗马上层社会的风尚。请回答：
（1）根据材料一、材料二，请问材料中提到的时间，当时中国是什么朝代？
（2）中国的“丝袍”是通过什么通道运转到欧洲的？请写出它的路线及为其开辟做出突出贡献的一个人物。
（3）今天，我国政府提出“西部大开发”战略，你能否利用这条交通路线给政府提些可行的建议呢？

      Florence Nightingale was born in a rich family.When she was young she took lessons in music and drawing，and read a lot of books.She also travelled a great deal with her mother and father.

      As a child she felt that visiting sick people was both a duty and a pleasure.She enjoyed helping them.At last her mind was made up.“I’m going to be a nurse，” she decided.“Nursing isn’t the right work for a lady，” her father told her.

       “Then I will make it so，” she smiled.And she went to learn nursing in Germany and France.When she returned to England，Florence started a nursing home for women.

      During the Crimean War in 1854 she went with a group of thirty-eight nurses to the front hospitals.What they saw there was terrible.Dirt and death were everywhere to be seen and smelled.The officer there did not want any woman to tell him how to run a hospital，either.But the brave nurses went to work.

      Florence used her own money and some from friends to buy clothes，beds，medicines and food for the men.Her only pay was in smiles from the lips of dying soldiers.But they were more than enough for this kind woman.

      After war she returned to England and was honoured for her services by Queen Victoria.But Florence said that her work had just begun.She raised money to build the Nightingale Home for Nurses in London.She also wrote a book on public health，which was printed in several countries.

Florence Nightingale died at the age of ninety，still trying to serve others through her work as a nurse.Indeed，it is because of her that we honour nurses today.

下列物体中，正在受到平衡力作用的是（   ）