What is something people can survive only a few days without?
Shelter Food O3 NaCl urea H20 H2O Salt
A B C D E F G H
Water is made up of H2O molecules.
Most people can survive only a few days without H2O
What is something people can survive only a few days without? (A) Shelter (B) Food (C) O3 (D) NaCl (E) urea (F) H20 (G) H2O (H) Salt