Acharasteristic that a living thing survive

Which process does not require the presence of a physical substance in order to transfer heat? air in the atmosphere is heated by the ground. this warm air then rises, and cooler air falls. this is an example of what type of process? how is conduction different from radiation?

When the mercury level in a barometer decreases that atmospheric pressure has

Calculate the percent composition by mass of each element in al(oh)3. use at least three significant figures.