Final answer:
The mass of air in a room measuring 5.0 m × 8.0 m × 3.0 m is calculated by multiplying the volume of the room by the mass of air per cubic meter, resulting in 153.6 kg.
Step-by-step explanation:
The mass of air in a room that measures 5.0 m × 8.0 m × 3.0 m can be calculated by first determining the volume of the room and then using the mass of one cubic meter of air to find the total mass. The volume of the room is found by multiplying the length, width, and height, which gives us 5.0 m × 8.0 m × 3.0 m = 120 m³. With the average mass of one cubic meter of air being 1.28 kg, the total mass of air in the room would be 120 m³ × 1.28 kg/m³ = 153.6 kg.