The ornamental design for a tread of a tire, as shown and described.
FIG. 1 is a perspective view of a tread of a tire embodying my new design,
it being understood that the tread pattern is repeated uniformly around
the circumference of the tread; and,
FIG. 2 is an end view of the tire tread design shown in FIG. 1.
In the drawings, the broken lines defining the tire inner bead and sidewall
are for illustrative purposes only and form no part of the claimed design.
The dark stippled surface shading represents the recessed portion of the
tread grooves, having a depth as best shown in FIG. 2.