The ornamental design for a kettle, as shown and described.
FIG. 1 is a perspective view of a kettle according to the present invention. The kettle is used to heat a liquid, such as water, for making a beverage, such as tea or coffee.
FIG. 2 is a left side view of the kettle of FIG. 1, the right side view being a mirror image thereof.
FIG. 3 is a top plan view of FIG. 1;
FIG. 4 is a bottom view of the kettle of FIG. 1.
FIG. 5 is a front view of FIG. 1; and,
FIG. 6 is a rear view of FIG. 1.
The broken lines of FIGS. 1-6 are for illustrative purposes only and form no part of the claimed design.