8.7 The vibrational energy is en = hw (n+), where n = 0, 1, 2,... and wis the vibrational frequency. (a) Show that Cvib k =e-Biha Bw 1- -e-Shoo Make a qualitative sketch of crib as a function of temperature. (b) Find the mean value (n+1) and mean-square fluctuation ((+)}-{n+.