Depends on what type of gun you are talking about. Generally speaking, few revolvers have safeties. Virtually all semi-automatic pistols and rifles do have them, and the majority of shotguns are now sold with a safety. Older lever-action rifles generally don't have safeties, and most bolt-action rifles don't either.
Yes, there are several. Most revolvers do not have (or need) a safety. Lever action rifles and guns with external hammers usually did not have safeties.
No, all guns do not have safeties. There are tens of thousands of different gun models, so it is impossible to say (in a brief answer) which ones do and don't. In GENERAL, most revolvers do not have safeties. Many single shot firearms do not (some do). The Glock auto pistol does not. Many lever action rifles with an external hammer originally did not- now they do. However, the most basic safety is safe handling of a firearm- assume any gun is loaded, do not point a gun at anything you do not intend to shoot, and keep your finger OUT of the trigger guard until you are ready to shoot.
all safeties are 2 points
No, they are not.
Safeties.
3
"Safeties" is the plural for safety.
Their weaknesses are their offensive line, their secondary on defense which is the cornerbacks, free safeties, and strong safeties. Their quarterback is also somewhat of a problem as well.
2
Safeties
cornerbacks/safeties