Rachel Jacobs, 39, New York City
Jacobs was chief executive of education technology firm ApprenNet, and she had been appointed to the post in March, according to the company's website. Jacobs was married and had a 2-year-old son, according to a family spokeswoman, and was originally from the Detroit suburbs. She also is survived by her parents, former Michigan state Sen. Gilda Jacobs and John Jacobs, and a sister.
She received an MBA from Columbia University and graduated from Swarthmore College, according to a family spokeswoman and a statement on the ApprenNet website.
In a statement released Thursday afternoon, the company said Jacobs "was not only a brilliant strategist, but also an extremely kind and loving person.... In addition to being our CEO, Rachel was our friend."
Her family called the derailment an "unthinkable tragedy."
"Rachel was a wonderful mother, daughter, sister, wife and friend," the family said in a statement. "She was devoted to her family, her community and the pursuit of social justice. We cannot imagine life without her."
-- Christine Mai-Duc