Will give BRAINLIEST How did the universe begin?

According to big bang model, the universe was born during a period of inflation that began about 13.8 billions years ago.  Like a rapidly expanding balloon, it swelled from a size smaller than an electron to nearly its current size.

Initially the universe was permeated only by energy, some of the energy congealed into particles, which assembled into light atoms like hydrogen and helium.

At first the atoms turned into galaxies, then stars and then other elements were forged.

Explanation:

These are what happened when the universe was forming.

Hope it helps.

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.