Final answer:
Time studies are updated periodically and the frequency depends on the business and industry. Work analysts or industrial engineers determine the time allotted for each category by observing and measuring workers' task completion time.
Step-by-step explanation:
Time studies are typically updated periodically, such as annually, to account for changes and improvements in work processes. The frequency of updates depends on the specific business and industry. To determine how much time is allotted for each category, a work analyst or industrial engineer observes and measures the time it takes for workers to complete tasks within the categories. They may use techniques such as time-motion analysis, work sampling, or predetermined time standards to accurately determine the time allocation.