A set of 13 particles occupies states with energies of 0, 100, and 200 cm^-1. Calculate the total energy and number of microstates for the following energy configurations.
a. a0= 8, a1= 5 and a2 = 0
b. a0 = 9, a1 = 3 and a2 = 1
c. a0 = 10, a1 = 1 and a2 = 2