Ellen is a criminalist collecting fiber evidence from a murder scene. She notices fibers on the victim's shirt and skirt, so she places both of these items of clothing in a plastic bag. She also sees fibers on a sheet near the victim, so she bunches up the sheet and places it in a separate plastic bag. Noticing fibers adhering to the door frame where the attacker gained entrance, she carefully removes them with her fingers and places them in a mailing envelope. What mistakes, if any, did Ellen make while collecting this evidence?