Edit opens the entry so you can fix it. Delete removes the row from the log (asks to confirm first).
This only changes the % shown. Your money in and out is not touched. If you bought more or sold some, also add a cash entry for it.
This permanently deletes the saved copy, so this business can no longer be restored. Your current businesses and logs are not touched. This cannot be undone.
The business and its saved entries come back exactly as they were when removed. Your other businesses and entries are not touched.