Aquality assurance manager is assessing the capability of a process that puts pressurized grease in an aerosol can. the design specifications call for an average of 60 pounds per square inch (psi) of pressure in each can with an upper tolerance limit of 65 psi and a lower tolerance limit of 55 psi. it is known that cans have an average of 60 psi. if the quality assurance manager wants to ensure that the fraction of cans that do not meet the specifications is as low as 2x10-9 (=0.2), what should be the standard deviation of the process?