The ornamental design for a taskchair, as shown and described.
FIG. 1 is a right side elevation view of a first embodiment of a task chair showing my new design, wherein the left side elevation view is a mirror image thereof;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a top plan view thereof;
FIG. 4 is a rear elevation view thereof;
FIG. 5 is a bottom plan view thereof;
FIG. 6 is a right side elevation view of a second embodiment of a task chair wherein the left side elevation view is a mirror image thereof;
FIG. 7 is a front elevation view thereof;
FIG. 8 is a top plan view thereof;
FIG. 9 is a rear elevation view thereof; and,
FIG. 10 is a bottom plan view thereof.
The broken line showing of portion of the task chair is included for the purpose of illustrating environmental structure and forms no part of the claimed design.