The time scale was first assembled using fossils and

Relative and absolute dating.

Explanation:

The clues in rocks help scientists to know how Earth has changed. The geologic time scale was crated by scientists observed that classified and studied fossils from the oldest to the youngest sedimentary rock in what is called relative dating. After years of research they started to implement absolute dating, which consists on measuring the amounts of radioactive elements in rocks  to determine the actual number of years old. The geologic time scale is divided into eons, eras, periods, and epochs.

but whats the question? ?

explanation:

populist movement, in u.s. history, politically oriented coalition of agrarian reformers in the middle west and south that advocated a wide range of economic and political legislation in the late 19th century. thus in 1892 their leaders organized the populist, or people's, party, and the farmers' alliances melted away.