(a) an ideal quantum gas comprises non-interacting identical partieles with discrete quantum states labelled 1, 2, possessing energies e1 for which the occupation numbers are nı, partition function is given by z(t. v,n)- lexр(-b (ms, +п,8, +}. explain why the partition function may be written 1 zgh.(t, v)= 1-exp(-e, ) rl [3 marks] (b) show that the mean occupation number is given by n = еxp (be, ) -1" 1aln z without proof.] [you may use the result n = де; )т. е, (rei) 3 marks] (c) describe the procedure for deriving planck's radiation law: hodo de -и (о, т) do- v псеxp (bho) -1| [4 marks a detailed derivation is not required