Answer:
The Earth is made up of many rocky layers. .
Explanation:
The solid, outer layer is called the crust. Below the crust lies a layer of very hot, almost solid rock called the mantle
The appearance of fossils would the the answer.
Although there has been some scientific debate about what fossil strata should mark the beginning of this period, the "International Geological Congress" determined that the Cambrian period was approximately 543 million years ago of which the first appearance in the fossil record of worms that made horizontal burrows was discovered.
Luminosity or magnitude of energy brightness
Any factor that causes distortion of genetic predictions.
