Arrange the events of the big bang in sequential order.

1. The universe comes into existence as a single point.

It is considered that the universe was created as a very hot and dense and as a single point in space.

2.  The universe begins expanding, and nuclear forces develop.

The four fundamental forces: electromagnetism, weak nuclear force, strong nuclear force and gravity were formed.

3. Atomic nuclei form.

Universe started to expand, became cooler and less dense. Protons and neutrons collided to make deuterium - an isotope of hydrogen

4. Hydrogen fuses into helium.  

Formed deuterium atoms combined to form helium.

5. The first neutral atoms form  

When matter in the universe cooled enough, electrons combined with nuclei to form neutral atoms

6. The universe is transparent.

In the phase "recombination," the absorption of free electrons caused the universe to become transparent.

7. Gases form that will later go on to shape the stars and galaxies.  

This is the phase of reionization, where gases collapsed enough to form the very first stars and galaxies.  

Explanation:

should proboly change a few words here and there

the pronoun reference replaces a noun, but you have to make sure there's no room for confusion.

in the first sentence "her" could be referring to shely or to the sister. the answer there is "shelly called her sister and told her about the new baby."

in the second sentence "it" could be referring to the roof or the floor. the answer there is "since the roof leaks on the family room floor, we need to repair the roof."