Facebook (NASDAQ:FB) COO Sheryl Sandberg will speak Monday with military women and top defense officials about challenges in the workforce. The discussion comes as the Marines question the effectiveness of women in combat roles. Defense Secretary Ash Carter and Facebook's COO are meeting along with 12 military women for "Lean in Circle" to talk about challenges and opportunities they face in the workforce. Sandberg is the author of the book "Lean In" and is the first woman to serve on Facebook's board. Facebook shares rose 0.6% to 94.97 in the stock... More