A reaction vessel at 27 C contains a mixture of SO₂ (P= 3.00 atm ) and O2(P= 1.20 atm ). When a catalyst is added the reaction 2SO₂(g)+O₂(g) ⇋ 2SO₂(g) takes place. At equilibrium, the total pressure is 3.95 atm.

a. Find the value of Kc. Express your answer using two significant figures.