In March of 1999, Bertrand Piccard and Brian Jones attempted to become the first people to fly around the world in a hot air balloon. Based on an average speed of 97.8 kilometers per hour, the distance that they traveled in kilometers, d, can be modeled by
d(t) = 97.8t, where t is the time in hours. They traveled a total of 478 hours.
Select the option that represents the domain of the function d(t).