We use the unique patterns every day to help us solve crimes, identify genetic features, keep track of inventory, and more. Astronomers use the unique patterns that atoms and molecules have in spectra to find the composition of stars. Why is it important that the patterns be unique?

Choose one or more:
A. We can figure out the compositions of distant stars just by looking at their spectra.
B. By counting the number of lines present in a spectrum, one can tell where the star is located in space.
C. The relative brightness of just a single line from an element in a spectrum gives us the age of a star.
D. The unique patterns serve as unmistakable “fingerprints” of the atoms and molecules present.

"Hundred Family Names" is one of the most popular and widely circulated textbooks in China. Its completion and popularity were earlier than "Three-character Classic". According to the research of Wang Ming-qing, a scholar of the Southern Song Dynasty, the first few surnames in the book are arranged in a particular way: Zhao refers to Zhao Song, and since it is the surname of the king, it should be the first; Secondly, Qian was the surname of the king of Wuyue in the Five Dynasties and ten Kingdoms. Sun was the surname of the Zhengfei of the then king Qian Chu; Li was the king of the Southern Tang Dynasty. He judged that "Hundred Family Names" seemed to be written by Xiaomin in the two Zhejiang dynasties. According to historical records, after the founding of the Song Taizu, Wu Yue still existed for some time, until the Song Taizong Xingguo two years before the rate of land surrender. It can be seen that this book was published in the early Northern Song Dynasty.

According to legend, "Hundred Family Names" was originally a private school reading book compiled by a scholar in Qiantang (Hangzhou) in the early Northern Song Dynasty, and the common family names were written into four characters and one sentence, like a four-character poem, which was then read and memorized. The "Hundred Family Names" originally collected 411 sutra donations to 504 family names, of which 444 were simply due to family names and 60 were repeated

It came out in the early Northern Song Dynasty

According to the research of Southern Song scholar Wang Ming and Qing, the first few surnames of the book

The arrangement is exquisite: Zhao refers to the Zhao Song Dynasty, since it is the king's surname should be first; Secondly, Qian was the surname of the king of Wuyue in the Five Dynasties and ten Kingdoms. Sun was the surname of the Zhengfei of the then king Qian Chu; Li was the king of the Southern Tang Dynasty. He judged that "Hundred Family Names" "seems to have been written by the small people when the Qian family had a state in two Zhejiang provinces". According to historical records, after the founding of the Song Taizu, Wu Yue still existed for some time, until the Song Taizong Xingguo two years before the rate of land surrender. It can be seen that this book was published in the early Northern Song Dynasty.