Heat can never flow from . . a.. hot to cold. . b.. cold to hot. . c.. liquid to solid. . d.. solid to liquid

Gymnast always perform on padded mats. how does the mats protect the gymnast

How many moles of air are there in a human lung with a volume of 2.4 l at stp? explain your answer

On the periodic table, elements are arranged by which of the following. a. mass numbers. b. increasing atomic number. c. alphabetical order. or d. density