The ornamental design for a sandal with removabletop, as shown and described.
FIG. 1 is a side perspective view of a sandal with removable top showing my new design;
FIG. 2 is another perspective view thereof.
FIG. 3 is a top perspective view thereof.
FIG. 4 is a right side view thereof; and,
FIG. 5 is a left side view thereof.
The unshaded regions form no part of the claimed design. The broken lines showing the remainder of the sandal are for environmental purposes only and form no part of the claimed design.