Lab Answers To Dna Fingerprints Biology Questions Please Help?

Biology Questions Please Help? - lab answers to dna fingerprints

This is a lab for gel electrophoresis.

Why a series of bands in the gel?

Why are the largest group of DNA fragment, which is closest to the hole where it was?

What if the electrodes were connected to the outputs of evil?

And I'm not sure what this question is asked.

"Why are the fingerprints of DNA be conclusively prove the innocence of a person and not his fault?"

Please, I have tried to answer these hours. I'm not posting on Yahoo, unless you really need.

Thank you.