A toy and a method for washing a body of an individual are provided. Also, a nonvolatile ferroelectric memory is applied to a FPGA, thereby preventing leakage of internal data and reducing the area of a chip. The opposing parallel wheels are attached to corresponding struts, which in turn are independently pivotably mounted near the longitudinal centerline of the frame, and are rotatable in a plane perpendicular to the rotationary plane of the two sets of wheels. A circuit for combining the first and second digital signals as a digital output signal for the data converter that represents the difference between the analog signals on the positive and negative analog input terminals.