It is now past the normal dinner time, but you do not even want to think about food. only diarrhea, abdominal cramps, and vomiting are on your mind. this all started a couple of hours ago in the early evening, after having a ham sandwich for lunch bought at a kiosk out on the street. since you have had microbiology, you surmise that it is a staphylococcus aureus-related disorder. why do you think this?