Why are cockroaches so hard to kill

I don't get it they are so small but can survive explosions why?

It's you raper again.
They can survive up 1000 higher dose of radiation than humans, because radiation destroys dividing cells, while cockroach's cells divide very rarely, unlike ours which divide as we type.

they are not hard to kill at all.
ill tell you a secret:
all you have to do is pick up your foot and step on them:)
or swat..your choice:)

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