Provide a numerical answer to each of the following questions and also show the calculations you used to find the answers.
How many different ways can 30 runners place in an Olympic qualifying marathon?
If only the eight fastest runners advance to the Olympics; how many different ways can the eight fastest runners be chosen from the whole field of 30 runners?
If the runner in first place receives a gold medal, the runner in second place receives a silver medal and the runner in third place receives a bronze medal; how many different ways can the three medalists be chosen from the whole field of 30 runners?