Deleting Submissions, Edit, Re-Submit??

[Ariah]

I have two articles that have been accepted, but not sold.

1. Can I delete the files from CC so I can edit them?

2. Do I have to go through the submit process again?

Also, I edited a third article, but it was in the long summary area. What do I have to do to make the change in the file? ...I'm guessing 1 & 2?