(1) Basic about sets:

       * Rosen 2.1: #11
       * An exercise with set builder notation (to be given in DGD)
       

(2) Set operations and identities:

       * Rosen 2.2:  #19a using (i) Venn diagrams, (ii) membership table, (iii) rigorous proof
       * SE 4.5a using (i) set identities  and (ii) membership table
       * SE 4.5c, e
       * Rosen 2.2: #30bc (Give a counterexample in (b); give a rigorous proof of (c).)
       

(3)  Selected problems from Midterm 1