What is the setting for the beginning of Act Three? Give a brief description of this place.

It is Mrs. Higgins's at-home day. Nobody has yet arrived. Her drawing-room, in a flat on Chelsea embankment, has three windows looking on the river; and the ceiling is not so lofty as it would be in an older house of the same pretension. The windows are open, giving access to a balcony with flowers in pots. If you stand with your face to the windows, you have the fireplace on your left and the door in the right-hand wall close to the corner nearest the windows.