Final answer:
To calculate the percentage of fans who downloaded the Radiohead release 'In Rainbows' from the band's website and paid nothing, we need more information than what is given in the question.
Step-by-step explanation:
To find the percentage of fans who downloaded the Radiohead release 'In Rainbows' from the band's website and paid nothing, we need to compare the number of fans who paid nothing to the total number of fans who downloaded. In order to do this, we need more information than what is given in the question. We know that 80 out of 571 participants in a survey download music weekly, but we don't know how many of them downloaded the Radiohead release 'In Rainbows' or how many of them paid nothing for the download. Without this information, we cannot calculate the percentage accurately.