Recently ranking near the top of the Forbes list of the worlds most powerful women was Sheryl Sandberg, the COO at Facebook. As Facebooks chief operating officer since 2008, Sandberg has helped dramatically boost revenues at the social network. Sandberg also founded Lean In, a nonprofit named after her bestselling book, to support womens empowerment. What are Sheryl Sandbergs primary sources of power? Explain with theoretical support and business approach.