Best Answer: Hi, Answer: estÃ¡ means is. Comments: There are two words for is in Spanish: estar and ser. EstÃ¡ is the third person singular, present indicative ...
The Largest division in the geological time scale is the Precambrian Era.It lasted from around 4.6 billion years ago to 570 million years ago.
There are 4 Eons on the geological time scale in total. Era - 12 total, spanning several hundred million years each. Period - a timespan longer than an Epoch, but shorter than an Era. Epoch - spans tens of millions of years each. All of these time spans relate events recorded in the stratigraphy to a certain point (or span) in the history of the Earth.