The ornamental design for a scale, as shown and described.
FIG. 1 is a perspective view of scale embodying the present design;
FIG. 2 is a front elevation view of the scale of FIG. 1; and,
FIG. 3 is a right side end view of the scale of FIG. 1.
The left side of the scale is nearly mirror to the right side and does not embody any additional portion of the claimed ornamental design. The rear and bottom of the scale do not embody any portion of the claimed ornamental design.