In a multi-screen display apparatus according to the present invention, a master image display apparatus acquires determination results obtained by an input detector and acquires a video signal of which channel is selected by a selector from each of a plurality of image display apparatuses including the master image display apparatus. The electronic device includes a display having a first area and a second area functionally divided, a determination module configured to determine a location of a touch input, and a processing module configured to process the touch input based on a state of the electronic device, if the location of the touch input is in the second area. Fresh air is drawn through vents in the latrine housing and thereafter through toilets in the latrine and through the vault, providing oxygen for the reaction. High-energy short wavelength light mixes with the longer wavelengths light to produce a broad spectrum which may be perceived by human observers as white light. This reduces beats in a particular channel, and prevents deterioration of picture quality in other channels. The connector socket is installed on the motherboard, and two latching portions are formed on two sides of the connector socket respectively.