hummmmmmmmm hmmmmmmmmmm
om
You would spell it 'hear' if you are referring to a sound that you listen to.
B A N G.
vroom
Eww.
There are many ways to spell the "ooh" sound. You can spell it oh, or uh. This depends on exactly what sound it is making.
It would mostly be like krack or Snap
The sound a goat makes is typically spelled "maa" or "bleat."
The sound of a stick hitting the ground is often spelled as "thud" or "whack."
Sound of electricity
You spell it with z, the reason why is because when you take s and put it in organize it would not look or sound the same.