Chem Titration need help urgent

Question

One of the titration curves in the diagram represents the titration of an aqueous sample of Na2CO3 with strong acid; the other represents the titration of an aqueous sample of NaHCO3 with the same acid. Which curve is Na2Co3 and which curve is NaHCO3

Identify the structure(s) observed at each point (a–c) indicated along the titration curve. Be sure to identify only the main carbon-containing species

Here is the graph : https://imgur.com/a/fvwnFZr. Thank you!

Answer 1

The RED curve is for Na₂CO₃ (CO₃^2- + H⁺ ==> HCO₃^- + H⁺ ==> H₂CO₃)

The BLUE curve is for NaHCO₃ (HCO₃^- + H⁺ ==> H₂CO₃)

Since there is only a, b, and c labeled for the red curve, I'm assuming that's all the question relates to, so here is what i find ...

Structures present at a = CO₃^2- and HCO₃^-

Structures present at b = HCO₃^- and H₂CO₃

Structure present at c = H₂CO₃