In frost bite, skin becomes hard black in about :: (A) 3 days, (B) 7 days, (C) 2 weeks, (D) 4-6 weeks
Answer is C. C i.e. 2 weeks Trench (immersion) foot results from prolonged exposure to severe cold (5 -8degc) of dampness. Frost bite occurs d/t exposure to greater extremes of cold (-2.5degc), develops more rapidly, & may affect other pas such as nose, ears. Skin becomes hard & black in 2 weeksQ (after initial blanching & paleness erythema & edema bisters).