Keyboard

FIG. 1 is an isometric view of a top, front, and right side of an ornamental design for a keyboard;

FIG. 2 is a top plan view of the keyboard of FIG. 1 ;

FIG. 3 is a bottom plan elevational view of the keyboard of FIG. 1 ;

FIG. 4 is a right side elevational view of the keyboard of FIG. 1 ;

FIG. 5 is a left side elevational view of the keyboard of FIG. 1 ;

FIG. 6 is a front elevational view of the keyboard of FIG. 1 ;

FIG. 7 is a rear elevational view of the keyboard of FIG. 1 ; and,

FIG. 8 is a perspective view showing the keyboard in an exploded configuration with a disclaimed cover shown for illustrative purposes.

The dash-dash-dash lines illustrate portions of the keyboard that form no part of the claimed design.