A navigation apparatus includes a base unit fastenable to a dashboard at a driver’s seat of a vehicle, a front panel unit attachable to and detachable from the base unit and with a display displaying map data, and a microcomputer adapted to perform a navigation function to indicate a determined location of the vehicle on the map data. The charging rate and the charge maintenance of the electrophotographic carrier can be preserved if the carrier composed of magnetic core particles and the resin coat satisfies the following equation >31, wherein represents a carbon content of the carrier and represents a ratio of the square root of the number of emitted photoelectrons ) and the photon energy. Determination is made as to whether a length 1 of the sheet of paper is shorter than a distance L1 between a second transfer roller and a fusing unit. A distance between inner segments of the notches is a function of the length of the wires such that an inline control panel and a junction splitter of the earphone set are positioned within a periphery of the retaining clip. The back side is formed to correspond to a shape of, and to be coupled to, the leading front edge. If a garbage collection does not occur, the fact that the local variables are declared pinned is ignored.