Exactly 10 Mol N₂O₄ Is Placed in an Empty 1

Exactly 1.0 mol N₂O₄ is placed in an empty 1.0-L container and allowed to reach equilibrium described by the equation N₂O₄(g) 2NO₂(g) .If at equilibrium the N₂O₄ is 28.0% dissociated,what is the value of the equilibrium constant,K_c,for the reaction under these conditions?

A) 0.44
B) 2.3
C) 0.31
D) 0.78
E) 0.11