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.
(b). Geologic Time. Geologists and geomorphologists describe the Earth's geologic history through a temporal system known as the geologic time scale (Table 10b-1). On this scale, time is measured using the following four units of time: eons, eras, periods and epochs.