Fact 1: Energy is used for heating a building by a heating system.

Fact 2: Each system is equipped with a control, a heat producer, a heat exchanger, and a heat distributor.

Given the two facts above, answer the question "buildings use a combination of production, exchange, and distribution of energy to for what" with the following options: 
- energy usage
 - consumers
 - ventilation
 - views
 - survival
 - temperature
 - Quality of life
 - water


 

      temperature   