A trial power toothbrush designed to emulate the performance of a corresponding commercial toothbrush, powered by a non-rechargeable battery. The printing apparatus also has a rotatable backing roller disposed adjacent the printing roller so that the moving web on which ink is to be applied passes between the backing roller and the printing plate as the backing roller and the printing roller rotate so that a printed image is applied to the web. 50 in water, an alkali metal salt of said acid and an alkaline earth metal of said acid; or a cellulose acetate containing an alkali metal or an alkaline earth metal wherein the total content of an alkaline metal and an alkaline earth metal in 1 gram of the cellulose acetate is from an effective amount to 5. The at least one intermediate result corresponds to a partial window aggregation. In one embodiment, the LNG is pumped to higher pressures and converted to dense phase natural gas prior to being transferred into the heat exchanger and the uncompensated salt caverns. The method comprises the steps of providing a flow restricting section having a cross sectional area and a length, measuring the flow resistivity of the flow restricting section, and modifying the cross sectional area andor the length of the flow restricting section until a desired flow resistivity of the flow restricting section is obtained.