Final answer:
A well-managed PACS should be up and running 99% of the time.
Step-by-step explanation:
A well-managed PACS should be up and running 99% of the time. This means that the system should be available for use for almost all of the time, with only minimal downtime for maintenance or upgrades. In a 99% uptime scenario, the system would only be unavailable for a maximum of about 3.65 days in a year, which is a relatively small amount of time.