If you are doing AQA spec, then you would know these from AS and GCSE.
Group 2 metal hydroxides solubility in water increase down a group.
Group 2 metal sulfates solubility in water decrease down a group.
Halides are mainly soluble, AgCl is an exception.
When CO2 is released, it hints that there may be a CO3 ion component in the compound.
With these information, the identities of the compounds can be found.