Yes
No, a pellet gun can't kill a bear it will only make it angry. There for it will eaither attack you or just ignore it.
It is passable to kill a cat in the right situation.
Yes
If you are talking about a PCP (PreCharged Pneumatic) rifle. With a .45 caliber pellet, then "Yes" It can. I don't believe there is a 40 Caliber pellet gun.
This is a great excuse to buy a pellet gun. Just buy one that has about 1000fps and in the early moring at about sunrise watch for the groundhog and if you can get within shooting distance go ahead and use it.
Yes. Under the right circumstances.
It is possible, Yes, But it depends on the caliber, Weight of the pellet, the FPS of the gun. I suggest using a Pellet rifle not a pellet gun. I suggest a head shot using hollow point pellets. Also a license may be required to hunt the goose
Depending on where you live and the local law. Yes a pellet gun will kill a squirrel. I suggest you use "Hollow point" hunting pellets.
Yes or any small rodent.
Given the right set of circumstances, yes.
Depends on the pellet gun, the distance, and the game laws where you live. Most pellet guns should not be used to hunt anything bigger than a squirrel. They do not have enough energy for a humane kill.