Question 1
Observation: My computer is running slowly. It could have a virus, too many programs running, or low disk space.
Which is the most reasonable inference about the cause?
This is abductive reasoning (inference to the best explanation). Given the observation 'My computer is running slowly. It could have a virus, too many programs running, or low disk space.', we consider possible causes and select the most plausible one. Too many programs are probably running (most common user issue) is the best explanation because it's the most common, simplest, or most likely cause.