Non-repudiation of two-party data is provided by operating a terminal to provide non-repudiation in respect of data exchanged between the terminal and at least one other terminal. The magnet set is fixed at the corners inside the outer-holder. A power circuit provides an output voltage and an output current to an output terminal; and it generates a current-sense signal according to the output current. The feeding device has a supporting member which can support the developing device pulled out toward the first position. Upon completion of the task, deliverables may be transmitted from the selected electronic device to a predetermined destination.