The ornamental design for a hat, as shown and described.
FIG. 1 is a front-left perspective view of the hat according to the claimed design;
FIG. 2 is a front view of the hat of FIG. 1;
FIG. 3 is a rear view of the hat of FIG. 1;
FIG. 4 is a right side view of the hat of FIG. 1;
FIG. 5 is a left side view of the hat of FIG. 1;
FIG. 6 is a top view of the hat of FIG. 1; and,
FIG. 7 is a bottom view of the hat of FIG. 1.
The features shown in broken lines, including stitching, seams, and the mesh portion of the crown, depict portions of the hat which form no part of the claimed design.