I claim the ornamental design for a hat, as shown and described.
FIG. 1 is a top, right, front perspective view of a hat according to my new design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a left side elevation view thereof, the left side elevation view being a mirror image of the right side elevation view;
FIG. 5 is top plan view thereof; and,
FIG. 6 is a bottom plan view thereof.
The indicia appearing in FIG. 2 and the other broken lines shown on the hat in all the figures illustrate environmental subject matter and form no part of the claimed design.