Answer to Question 1
Any three of the following:
Hands that touch raw foods, such as chicken, then touch food that will not be cooked, like salad ingredients
Surfaces, like cutting boards or cleaning cloths, that touch raw foods, are not cleaned and sanitized, then touch readytoeat food
Raw or contaminated foods that touch or drip fluids on cooked or readytoeat foods
Raw and ready-to-eat foods are improperly stored in a refrigerator
Answer to Question 2
A rule of thumb for the numbers of organisms required to produce toxins or to produce desired or undesired flavors is 1 million per gram.