Use 2-inputs NAND gates only and Boolean algebra theorems to design a logic circuit that controls safety system of a residential building. The logic circuit's inputs are connected to building's smoke...

Use 2-inputs NAND gates only and Boolean algebra theorems to design a logic circuit that controls safety system of a residential building. The logic circuit's inputs are connected to building's smoke detectors (A, B &C). The logic circuit will trigger a Fire Fighting System whenever 2 (or more) smoke detectors are activated.