Grains are rich in what nutrient?

You did not show us the image of the burger, but i shall try to answer as best i can.  when purchasing food, always consider the ingredients as well as the person who prepared it. consider if they were hygienic people or not, in case the burger was infected with bacteria. no mortal should place an infected burger into their mouth.   

It is less likely that the shoe will slip while someone is walking

Do you have a picture for this question?

Yes i have used it before