The ornamental design for a seat, as shown and described.
FIG. 1 is a front perspective view of a seat showing my design in the form
of a sofa;
FIG. b 2 is a front perspective view of my design shown in the form of a
love seat; and
FIG. 3 is a front perspective view of my design shown in the form of an
armchair.
The sides of the seat forms not shown are mirror images of the respective
sides shown while the undisclosed rear surfaces thereof are conventional
in appearance.