This compound is a powerful oxidizing agent and a harmful ...

[EY67]

This compound is a powerful oxidizing agent and a harmful pollutant; yet a layer of it in the upper stratosphere serves as a shield from harmful ultraviolet radiation from the sun.
 
  A) CO2
  B) O2
  C) SO3
  D) O3 (ozone)

Question 2

If we should run out of aluminum someday, it would be because we had
 
  A) converted too much aluminum to another metal.
  B) destroyed too much aluminum.
  C) used too much aluminum.
  D) scattered aluminum too widely in the environment for efficient recovery.

[ong527]

Answer to Question 1

D

Answer to Question 2

D

[EY67]

Excellent

[vickyvicksss]

Gracias!