You will be given a definition of a task first, then some input of the task.
In this task, we ask you to write an answer to a question that involves “event duration", based on a given sentence. Here, event duration is defined as the understanding of how long events typically last. For example, “brushing teeth”, usually takes a few minutes. Note that a lot of the questions could have more than one correct answer. We only need a single most-likely answer. Please try to keep your "answer" as simple as possible. Concise and simple "answer" is preferred over those complex and verbose ones.

Sentence: The 300-millimeter silicon wafers -- about the size of a standard pizza -- are shuttled around the facility in enclosed plastic pods, which ride on overhead tracks. 
Question: For how long do the wafers ride on tracks?
Output:
5 hours.