The ornamental design for a lever of an arm of a stand, as shown and described.
FIG. 1 is a front elevation view of a lever of an arm of a stand showing our new design, wherein the arm of the stand is shown in a first position relative to the stand which are illustrated as environmental subject matter;
FIG. 2 is rear elevation view thereof;
FIG. 3 is a left side elevation view thereof, wherein the right side elevation view is a mirror image of FIG. 3;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof;
FIG. 6 is a front right isometric view thereof, further illustrating a display on the stand as environmental subject matter;
FIG. 7 is an additional left side elevation view thereof, wherein the arm of the stand is shown in a second position relative to the stand, and wherein the corresponding right side elevation view is a mirror image of FIG. 7; and,
FIG. 8 is an additional front right isometric view thereof.
The broken lines in FIGS. 1 through 8 illustrate environmental subject matter and form no part of the claimed design.