Which among the following is NOT an example of salt of strong acid and weak base?

Find $$[\mathrm{OH}]$$ if a monoacidic base is $$3 \%$$ ionised in its $$0.04 \mathrm{~M}$$ solution.

What is the expression for solubility product of silver chromate if it's solubility is expressed as $$\mathrm{S} \mathrm{~mol} \mathrm{~L}^{-1}$$ ?

What is $$\mathrm{pH}$$ of solution containing $$50 \mathrm{~mL}$$ each of $$0.1 \mathrm{~M}$$ sodium acetate and $$0.01 \mathrm{~M}$$ acetic acid? $$\left(\mathrm{pK}_{\mathrm{a}} \mathrm{CH}_3 \mathrm{COOH}=4.50\right)$$