A device for dielectrophoretic manipulation of suspended particulate matter comprises an analysis electrode and a separate cover electrode wherein the analysis electrode comprises an electrically conductive layer of material provided on a substrate support and apertures are defined through the electrically conductive layer. Questions in the sequence of questions may relate to an insurance underwriting function. A pair of support members are engaged together in different orientations, to raise the elevation of the wheel engagement structure of the upper support member above the supporting surface and to enable the user to adjust the angle of the bicycle. The light emitting surface and the light guide surface extend in a direction substantially parallel to the direction of the light received from the light source. The spigot assembly is of a multiple part construction such that it substantially avoids entrapment of either sediment or air in or on the assembly as the spigot operates to remove liquid from the vessel.