JOPLIN, MO – Oct. 13, 2014 – “What is in my hamburger?” “What part of the chicken is a Chicken McNugget™?” “Why are the fries so good?”McDonald’s USA will answer these questions and more from customers, fans and food skeptics through a multifaceted effort called “Our Food. Your Questions.” Starting today, the company invites people to submit their food questions via social media. McDonald’s will respond with behind-the-scenes webisodes and other social content that provides facts on ingredien…