The present invention includes a wireless mobile communication device with a body casing having an exterior surface, and a number of light sources disposed on the exterior surface. In one embodiment, the sensor is a P sensor for sensing a differential pressure across a flow restriction mechanism disposed between an exhaust manifold and an intake manifold of an internal combustion engine. The operating voltage for the microprocessor core is selected to satisfy power and performance criteria while the operating voltage for the memory block is set to provide acceptable noise margins and maintain stability of the memory cells within the memory block. Various illustrative techniques for managing a power-efficient data center are also described. A nip position of the ejection rollers is arranged in a side opposite to a side where the document placing tray is arranged with reference to a vertical plane passing through a separation position of the separating mechanism. The present invention further pertains to ink set having this yellow ink.