At 700 K,K_p for the Following Equilibrium Is 5

Multiple Choice

At 700 K,K_p for the following equilibrium is 5.6 × 10^-3. 2HgO(s) 2Hg(l) + O₂(g)
Suppose 43.1 g of mercury(II) oxide is placed in a sealed 4.00-L vessel at 700 K.What is the partial pressure of oxygen gas at equilibrium? (R = 0.0821 L · atm/(K · mol) )

A) 0.074 atm
B) 0.0056 atm
C) 2.8 atm
D) 14 atm
E) 1.4 atm