An organizational psychologist conducted a study to see whether upgrading a company's older computer system to newly released, faster machines would cause an increase in productivity from the current average of 120 units with a standard deviation of 20. the new system is tested in a single department with 45 employees. the company has decided that anything less than medium effect will not justify purchasing the new system. what is the effect size for an increase to 130 units? what should the psychologist report to the company regarding purchasing the new system?