Potassium chloride and sodium nitrate reacts to produce potassium nitrate and sodium chloride

Ans. : frostbite is when exposure to cold temperatures causes freezing to the skin or other tissues. it most commonly affects the hands, feet, and face. the longer areas are exposed to cold, typically the worse the frostbite. the water temperature used for rewarming a frostbitten part should be : (102 -105) f degrees.

Ibelieve it is b. proton.hope my answer has you : )