A freelance computer consultant keeps a database of her clients, which contains the names S = {Acme, Bakers, Cores, Dual, Energy, Flavour, Global, Hilbert}. These clients owe her money:

A = {Acme, Cores, Energy, Global}.

These clients have done at least $2,000 worth of business with her:

B = {Acme, Bakers, Cores, Dual}.

These clients have employed her in the last year:

C = {Acme, Cores, Dual, Energy, Global, Hilbert}.

A subset of clients is described that the consultant could find using her database. HINT [See Example 4.]
The clients who do not owe her money or have employed her in the last year. Write the subset in terms of A, B, and C.

A. A' ∩ B
B. A' ∩ C
C. A ∪ C
D. A ∩ B
E. A' ∪ C

List the clients in that subset.

A. {Flavour, Bakers}
B. {Acme, Energy, Cores, Global, Bakers, Dual, Flavour, Hilbert}
C. {Acme, Energy, Cores, Global}
D. ∅
E. {Acme, Cores}