Answer:
Single Displacement Reaction: a reaction in which an element is swapped for another in a molecule
A + BC ---> AC + B
Double Displacement Reaction: a reaction in which the cation of one molecule is swapped with a cation of another molecule
AB + CD ---> AD + CB
a) Single Displacement Reaction
3 Ca + 2 AlBr₃ ----> 3 CaBr₂ + 2 Al
b) Single Displacement Reaction
2 Al + 3 MgSO₄ ----> Al₂(SO₄)₃ + 3 Mg
c) Double Displacement Reaction
AgNO₃ + KCl ----> AgCl + KNO₃