Answer
This dataset is a sample.
Work Step by Step
The population is the total number of spectators at the stadium, which is 42,000. If you take a survey of only 500 of them, then this is a sample of the total population. The answers that these 500 spectators give in your survey are representative of the total number of spectators, but may not exactly match the answers all 42,000 will give. For example, if 25% of your sample say that they like hot dogs, it may be the case that 26% of the population like hot dogs (had you surveyed all 42,000 of them). However, we can say that the survey of 500 spectators is a good enough indication of what the population distribution will look like.