How many different BCD numbers can be stored in 12 switches? (Assume two position or on-off switches)
- A. $2^{12}$
- B. $2^{12} - 1$
- C. $10^{12}$
- D. $10^3$
Answer: D. $10^3$
Explanation: 12 switches = 12 bits.\nBCD requires 4 bits per digit.\n$12 / 4 = 3$ digits.\n3 BCD digits can represent numbers from 000 to 999, i.e., $10^3$ numbers.