The ornamental design for a mirror, as shown and described.
FIG. 1 is a front perspective view of a mirror showing my new design;
FIG. 2 is rear perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a left side elevational view thereof;
FIG. 6 is a right side elevational view thereof;
FIG. 7 is a top plan view thereof;
FIG. 8 is a bottom plan view thereof;
FIG. 9 is a front perspective view of the mirror where the mirror is in an alternate configuration of use with the adjustable connecting rob is dismounted from the mirror body; and,
FIG. 10 is a rear perspective view of the mirror where the mirror is in an alternate configuration of use with the adjustable connecting rob is dismounted from a mirror body.
The broken lines in the drawings depict portions of the mirror that form no part of the claimed design.