The altitude at which we boil an egg affects how long it takes for the egg to achieve perfect hardness. It takes 198 seconds to boil a perfect egg at the lowest place possible, the edge of the Dead Sea, which has an altitude of −418 meters. The highest place possible is the summit of Mount Everest which has an altitude of 8848 meters. It takes 209 seconds to boil a perfect egg there. T(a) models the time (in seconds) it takes to boil a perfect egg at an altitude of a meters. Which number type is more appropriate for the domain of T? What's the appropriate domain?