In a room there are 12 bulbs of the same wattage, each having a separate switch. The number of ways to light the room with different amounts of illumination is
A. 122 − 1
B. 212
C. 212 − 1
D. none of these.
Answer:C
In a room there are 12 bulbs of the same wattage, each having a separate switch. The number of ways to light the room with different amounts of illumination is
A. 122 − 1 B. 212 C. 212 − 1 D. none of these.