ISO

Photo taken at ISO 3200

Photo taken at ISO 220

1. What are the advantages of shoot at a higher ISO at a sporting event like basketball or a night football game?
Well with a higher ISO you can actually see who is playing. If it were to be low at a sporting event then it will be hard to tell who is playing or what game is being playing. You get to see what is happening in the photo if the ISO is higher.

2. What suggestions did the author make about using a low ISO?
Try to stick to using base ISO so you can have a chance of getting a high quality photo with not too much noise in the photo.

3. What suggestions did the author make about using a high ISO?
You should only use it if you are unable to brighten the photo's shutter speed or aperture. Otherwise you should stick with base ISO. A photo taken at too high of an ISO will also show a lot of grain (noise)