In Central Africa, Ndembu warriors rub themselves with red paint during celebrations. Since their culture sees the color as a symbol of life and health, sick people are also painted with it. Like most Central African cultures, the Ndembu see red as ambivalent, better than black but not as good as white. In other parts of Africa, however, red is a color of mourning, representing death. Because red bears are associated with death in many parts of Africa, the Red Cross has changed its colors to <answer>green and white</answer> in parts of the continent.
What alternative colors does the Red Cross use in certain parts of Africa?
green and white