A Geiger counter used in several applications over the course of a typical day produces on the average 100 counts per second. The tube is in the form of a cylinder 5 cm in diameter by 20 cm long and is filled with a mixture of 90% argon and 10% ethanol to a pressure of 0.1 atmosphere. In the Geiger-Muller region, each output count results from the formation of about 1010 ion-electron pairs. How long will it take for one-third of the quenching gas to be used up, thus necessitating replacement of the tube