A hot-air balloon consists of a basket hanging beneath a large envelope filled with hot air. A typical hot-air balloon has a total mass of 554 kg, including passengers in its basket, and holds 2.62 10³ m³ of hot air in its envelope. If the ambient air density is 1.27 kg/m³, determine the density (in kg/m³) of hot air inside the envelope when the balloon is neutrally buoyant. Neglect the volume of air displaced by the basket and passengers.

_____kg/m³