9. four

11. (Continued)

Switch A or switch B may be either open or closed (O or 1

10. both

position). The series circuit will provide an output only if both A

switches

closed

and B are closed; i.e., equal to 1. If either switch A or switch B

is open (i.e., equal to 0), then the circuit will not provide an

circuit is AB.

Assuming there is a complete circuit for each of the following

switching circuits, the Boolean expressions representing the

output would be