The ornamental design for a seat, as shown and described.
FIG. 1 is a front perspective view of my ornamental design for a seat.
FIG. 2 is a rear perspective view of the design of FIG. 1.
FIG. 3 is a front elevational view of the design of FIG. 1.
FIG. 4 is a rear elevational view of the design of FIG. 1.
FIG. 5 is a side elevational view of the design of FIG. 1.
FIG. 6 is a top view of the design of FIG. 1; and,
FIG. 7 is a bottom view of the design of FIG. 1.
The broken lines in these drawings serve to illustrate the environment in which the claimed design is associated or serve to define the bounds of the claimed design. The broken lines form no part of the claimed design.