At temperature t = 0 k, which is true? a. 100% of the states below the fermi level are occupied and none of the states above it are occupied. b. 100% of the states above the fermi level are occupied and none of the states below it are occupied. c. most of the states below the fermi level are occupied and some of the states above it are occupied. d. most of the states above the fermi level are occupied and some of the states below it are occupied.