All three questions are identical in my opinion. The underlying point of the debate is:

Is 1 life worth many?

The answer to me is No. Granted, I'm human, and thus there is a certain weighted system I apply personally: Such as, if the 1 is my wife - you can stack up hundreds and get nothing out of me.

OTOH: Talking simply about strangers, I hold no imagination that I'm god. I do, however, have a logical mind and the way I see it is this.

The idea that life is priceless is actually incomprehensible because then obviously life equals other life. That is truly what it boils down, a mathematical equation. 1 == 1. No one life, at a fundamental level, is worth any more or less than any other life. Ted Bundy is worth no more or less than Albert Einstein. The operative here is what that life is worth to you.

Save 4 strangers; or allow 4 to die - I have a higher chance of getting at least worthwhile person in the lot of 5 . (although the reverse is also true, higher chance of saving a murderer/rapist/thief/general a-hole/etc).

To me, flipping the switch is worth it. Police Officers are faced with this sort or thing all the time.

Does a Police Officer shoot at a suspect who is armed and firing randomly into a crowd: Knowing full well that his bullet can miss and possibly hit an innocent bystander, including a child? IMHO - Yes.

I am also a former Military man and would not have survived without this mentality.