Answer
a. 65,536
b. 16,777,216
c. 16,777,216
Work Step by Step
a. 16-bit sampling can represent $2^{16}=65,536$ possible voltages.
b. 24-bit sampling can represent $2^{24}=16,777,216$ possible voltages.
c. For 3 subpixels, each requiring 8 bits, we use 24 bits. This is the same answer as before. The number of different colors is $2^{24}=16,777,216$.