Final answer:
The total mass of air inside the house at 20°C is 924 kg. The amount of air entering or leaving the house depends on whether the volume remains constant. If the volume changes, the amount of air entering or leaving can be determined based on the change in volume.
Step-by-step explanation:
To calculate the total mass of air inside your house, you need to determine the density of air and multiply it by the volume of your house. The density of air at 20°C is approximately 1.2 kg/m³. Therefore, the mass of air inside your house at 20°C would be 1.2 kg/m³ x 770 m³ = 924 kg.
If the temperature decreases to -10°C, the amount of air entering or leaving the house depends on whether the volume remains constant. If the volume remains constant, there will be no change in the amount of air inside your house. However, if the volume changes due to expansion or contraction of the air, you would need to account for the change in volume to determine the amount of air entering or leaving the house.