Dear Mr. Chang, I am worried about your proposal to install a groundwater heating system in my daughter’s school.
I don’t think that water at a temperature of 30°C has enough energy to heat the school. If the school is too cold, the students won’t be able to focus on learning.

Respond to David Li’s letter. Explain how the groundwater system could heat the air in the school. Explain what would happen to the air temperature at Riverdale School if the groundwater system were used. Use the terms stability and change in your explanation.