#1 Sodium Carbonate
#2 HCl
#3 Lead Nitrate
#4 Barium Nitrate
All you had to know was the Sodium Carbonate and HCl made the CO2 bubbles
All Group 1 Nitrates are Soluble (therefore Barium = no reaction)
Lead Nitrate forms a precipitate
So from those properties you can deduce and...