5. The specific heats of iodine vapor and solid are 0.031 and 0.055 cal/g, respectively. If the enthalpyof sublimation of iodine is 24.0 calg at 200℃, the enthalpy of sublimation of iodine at 250℃should be
(A) 24.0 cal/g,
(B) 26.4 cal/g,
(C) 20.8 cal/g,
(D) 28.6 cal/g,
(E) 22.8 cailg.