Answer:
The most recent eon is subdivided into three eras and eleven periods.
Explanation:
The geological time scale has been constructed so that it can help in better research and understanding of the past, as well as making it easier to distinguish the past and its characteristics at a certain time. There are larger and smaller divisions in the geologic time scale, with the eon being the largest unit, followed by era, and then period.
The most recent eon is the Paherozoic, starting from 542 million years ago and still going on. It is subdivided into three eras and eleven periods so far. The three eras are:
- Paleozoic
- Mesozoic
- Cenozoic
The eleven periods are:
- Cambrian
- Ordovician
- Silurian
- Devonian
- Carboniferous
- Permian
- Triassic
- Jurassic
- Cretaceous
- Tertiary
- Quaternary
The theory that explains the causes of earthquakes and volcanoes is plate tectonics
.
an animal that eats both plants and animals is an omnivore.
To find the epicenter (the point on the earth's surface where an earthquake begins) during earthquakes, one need to view the seismogram (a record of the ground motion), and at least two other seismographs recorded for the same earthquake. Other instruments such as a map, a compass for sketching circles on the map, a ruler, and a pencil will also be used.
The following are the steps of the triangulation process in the correct order to find the epicenter during earthquakes:
Step 1: Subtract the time of P wave arrival from S wave arrival.
Step 2: See what the time difference is equal to in distance on a seismic wave chart.
Step 3: Draw circles representing the distances from at least three seismograph stations to the epicenter on a map.
Step 4: Find the point where all 3 circles intersect, and you've found the earthquake's epicenter.
Answer:
20
Explanation:
180-160=20 simple degree subtraction
