Salt Lake City, Utah police haven't found her body yet, but they do have human tissue matching MacKenzie Lueck's DNA. MacKenzie's a University of Utah student, only twenty-three-years-old, who's been missing since June 20. That's the day her family filed a missing person report. MacKenzie, who's been very active on social media, hadn't posted anything since June 17. The last time she was seen, MacKenzie took a Lyft from Salt Lake City's airport to a city park. There she got i