Fact 1: Electricity sometimes is used for heating buildings.

Fact 2: Hospitals incorporate most types of technical systems encountered in other types of buildings.

Given the two facts above, answer the question "what is electricity sometimes used to heat?" with the following options: 
- space
 - hospitals
 - waves
 - direct energy
 - energy
 - Light
 - condensation
 - clouds


 

  hospitals       