Indicate a method or reagent$($s$)$ that could be used to distinguish between the following pairs of solids. State the expected results clearly.

$(24pts)$

a$.B{a}_3(P{O}_4{)}_2$ and $BaS{O}_4$

b$.BaC{O}_3$ and $BaS{O}_4$

c$.$ AgCl and $A{g}_{2}C{O}_3$

d$.(N{H}_4{)}_{2}S{O}_4$ and $N{H}_{4}Ac$