Warm drinks like tea are good, as long as it does not make them sick and cause choking; do not give if they are fainting. It is better to heat the body core first rather than put them in front of a fire.
Spot on. Insulate the body (space blanket, plastic anorak, blanket etc. Then a warm drink (not piping hot)
Huh! Good to know. In old romance novels, if the heroine had gotten lost in a snow storm, or some such danger, the hero would always warm her up with a glass of brandy. Oops!