What main criterion determines major divisions in the geologic time scale?

A. shifts in the position of Earth in its orbit

B. the occurrence of huge events in Earth's natural history

C. different stages in human evolution

D. times of major climate change

The answer is B. the occurrence of huge events in Earth's natural history

The geologic time scale is a system of chronological dating that relates geological strata to time. It is used by geologists, paleontologists, and other Earth scientists to describe the timing and relationships of events that have occurred during Earth's history.

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.

i do not get it   at all