按要求列举出下列答案。
— What do you do on the weekend?
— I often play _______ chess and sometimes I play ______ guitar.
②2H2(g)+O2(g) = 2H2O(g)；ΔH2= b kJ·mol-1 ③ H2(g)+ 12 O2(g)=H2O(l)；ΔH3= c kJ·mol-1
④2H2(g)+O2(g) = 2H2O(l)；ΔH4= d kJ·mol-1，下列关系式中正确的是（ ）
