Remember, the drug label will tell you: 1  what the drug is used for. 2  how to take the drug. 3  how to reduce the risk of drug interactions and unwanted side effects.
The units that divide the geologic time scale are Eons, Eras, Periods, and Epochs. Eons are the biggest, Eras are the second biggest and so on and so forth. So it goes Eons, E â¦ ras, Periods, and then Epochs. I know this because i just took a test on it in science so i know its right.
The Geologic Time Scale. The 4.55 billion-year geologic time scale is subdivided into different time periods of varying lengths. All of Earth history is divided into two great expanses of time. The Precambrian began when Earth first formed 4.55 billion years ago and ended about 570 million years ago.