The various atomic masses of the same element are called
a. neutrino
b. positron
c. critical mass
d. isotopes

The answer is d. isotopes. The same element must have the same protons. And the atoms with same protons and different neutrons are called isotopes.

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.