FIG. 1 is a front, side, and top perspective view of our design for a cap for an instrument for dispensing a composition;
FIG. 2 is a front elevation view thereof;
The rear elevation view thereof is the same as that shown in FIG. 2.
FIG. 3 is a side elevation view thereof;
The elevation view thereof, taken from the side opposite that in FIG. 3, is the same as that shown in FIG. 3;
FIG. 4 is a top view thereof; and,
FIG. 5 is a bottom view thereof.
The broken line showing of environmental structures is for illustrative purposes only and forms no part of the claimed design.