In the Diagram Below,helium Atoms Are Represented by Unshaded Spheres,neon

Multiple Choice

In the diagram below,helium atoms are represented by unshaded spheres,neon atoms by gray spheres,and argon atoms by black spheres.
-If the total pressure in the container is 900 mm Hg,what is the partial pressure of neon?

A) 90 mm Hg
B) 180 mm Hg
C) 270 mm Hg
D) 450 mm Hg