Final answer:
The rate of heat flow through the brick wall cannot be calculated without knowing the outdoor temperature. Therefore, we need to know the temperature outside to answer the question accurately.
Step-by-step explanation:
The brick wall of a home with a thickness of 25cm has a total area of 7m².
To find the rate of heat flow through the wall, we need to know the temperature difference between the indoor and outdoor temperatures and the thermal conductivity of the brick.
However, the outdoor temperature is not provided in the question, so we cannot calculate the rate of heat flow without that information.
Therefore, we need to know the temperature outside to answer the question accurately.