The ornamental design for a hat, as shown and described.
FIG. 1 is a front, top isometric view of the hat.
FIG. 2 is a lower, side isometric view of the hat of FIG. 1 showing possible wearing by a person shown in broken lines, said person forming no part of the claimed design.
FIG. 3 is a right side view thereof, the left side view being a mirror image of FIG. 3.
FIG. 4 is a front, plan view thereof.
FIG. 5 is a rear, plan view thereof.
FIG. 6 is a top, plan view of the hat of FIG. 1; and,
FIG. 7 is a bottom, plan view thereof.
Auxiliary item attachment structures, seams, the internal sweatband, neck straps and the crown size adjustment structure shown in broken lines in the figures are unclaimed features of the article in which the claimed design is embodied.