The brown stuff is called plaque. This forms on your teeth when you eat and its something you can't get rid of. There is tooth paste that can help maintain it.
Answer:
Dietitian
They are usually an exper on diet and nutrition
The best answer to fill in the blank would be ''Bystander'' because as that role you can go tell any adult or higher authority to stop the fighting so you don't try to be a hero and get yourself hurt as well.
1) C
2) A
all would be a risk due to swallowing puzzle pieces little kids put everything in their mouths. my thoughts
