We claim the ornamental design for a medical cart, as shown and described.
FIG. 1 is a perspective view of the medical cart.
FIG. 2 is a front view of the medical cart.
FIG. 3 is a left side view of the medical cart.
FIG. 4 is a right side view of the medical cart.
FIG. 5 is a rear view of the medical cart.
FIG. 6 is a top view of the medical cart; and,
FIG. 7 is a bottom view of the medical cart.
The broken line showing casters and interior compartment dividers is included for the purpose of illustrating a portion of the medical cart that forms no part of the claimed design.