The heat loss of a glass window varies jointly as the window's area and the difference between the outside and inside temperatures. A window 2 feet by 5 feet loses 3000 Btu per hour when the temperature outside is 30° colder than the temperature inside. Find the heat loss through a glass window that is 8 feet by 15 feet when the temperature outside is 15° colder than the temperature inside.The heat loss is ____Btu per hour.(Type an integer or a decimal.)