What volume does 2.81 mole of H, occupy at STP?

Sorry i dont understand the question can you rephase it?

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.

Use a magnet to separate iron, evaporate water, i'm not sure how to separate the other two i'm sorry but good luck

Answerchemical;