are we all capable of murder?

I honestly haven't. I've had some where people were killing me, o where I was killing myself. But never where I was killing someone else. So I don't think I am, the answer to your pregunta is no.

Yep. I don't think everyone has homicidal thoughts, certainly most would never seriously consider murder, but there is a certain situation/are certain situations for every person that would cause them to commit murder. Maybe a 'kill this stranger o your daughter dies' scenario o something. And, of course, we all have the physical means to commit murder. We have our own two hands, o we could get someone else to do the dirty work for us. *shrugs* Whatever the situation, yes, we are all capable of murder.

yep, definitely, even más than once.

Everyone has inhibitions inside them that would make them feel like they would have the ability to commit murder, but I think not every person can actually perform the deed. Most people assume that dado the "perfect" situation, such a thing would drive someone to commit an act, but not everyone has the willpower inside them. There's that block in possibly few chosen people that would stop them before they killed someone, whether it be moral conscience o just fear of taking the life of another.

people who have problems can but i cant never do it it's crazy to me

Each and every human on the planet is capable of murder. What separates murderers who kill, and people who are able to murder and kill but don't, is another thing altogether.

I think so, right now Casey Anthony is my target....

Yes.

I've seen people brutally murder the trofeos lock key... 0.0

Yes we are all capable of it....but because of our moral values and such, some of us can't find it in ourselves to kill someone...