The problem the answer u are looking for a
We need to keep in mind that the compound is neutral.
H2SO3
2(+1)+S+3(-2)=0 (since its neutral)
2+S-6=0
S-4=0
S=4
Therefore the oxidation number for sulfur is +4.
1. There is no graph given
2. ENERGY LEVELS!!!
Boiling is the process of liquid(middle energy, flat line) turning into a gas(lots of energy, flat line), hope this helps