A process for preparing potassium monoethyl malonate by selective saponification of malonic acid diethyl ester with potassium hydroxide, in which the potassium hydroxide is added to the malonic acid diethyl ester, malonic acid diethyl ester and potassium hydroxide are used in a molar ratio of at least 1. The apparatus is provided with mark display units 17 and 19 individually displaying a plurality of kinds of the treatments in respect of breeding the virtual creature individually by marks 17a, 17b, 17c. The service instances are encrypted using public andor private keys provided by service providers or central authorization agents. The lips, due to the dual angles, substantially and simultaneously drive panel metal into fastener grooves both longitudinally and laterally. The conveyor assembly further includes a second conveyor frame, connected to the first conveyor frame via a pivot, and configured to automatically rotate to change an angle between the first conveyor frame and the second conveyor frame in response to movement of the first conveyor frame relative to the mounting frame. The system comprises a central server operably connected to a network that comprises at least one processor and memory containing software executable by the at least one processor.