What is used to heat a building by a heating system?
engines wind insulation photons radiator body heat calcite ice
A B C D E F G H
Radiators are used to heat the building, The energy source is oil.
Radiators are used to heat a building by a heating system.
What is used to heat a building by a heating system? (A) engines (B) wind (C) insulation (D) photons (E) radiator (F) body heat (G) calcite (H) ice