Dana's life in the twentieth century? Or Dana's life when she travels through time? They are very different. In the first she is scholastic and intellectual; in the second she must do intense physical labor. In both, however, she is involved with a white man in some way, or rather, in many ways.
The fact that Dana is African American helps her because she has greater perspective on the period than a white man or woman might. The sixties and the Civil Rights movement are recent enough for her that she would have close memories of them, and how they were before. She would have experienced or heard of the last public remnants of that period, segregation. She would have had first or nearly first hand experience of how long change takes. Therefore, she has perspective, and knows she needs patience. As a woman, she's had to deal with male domination, or the potential for it. She knows power dynamics. Intellectual reflection, perspective, an understanding of power, and of course, compassion that surpasses race: these are the things she brought to helping this white man in the past.