The ornamental design for a chair, as shown and described.
FIG. 1 is a front perspective view of a chair showing my design;
FIG. 2 is a front elevational view; and
FIG. 3 is a side elevational view thereof.
The side of the chair not shown is a mirror image of the side shown in FIG.
3 while the undisclosed rear surface of the plural slat members are
conventionally flat and unadorned.