Hi,
Homogeneous mixture 2
Heterogeneous 3
Mixture 1
Solution 5
Compound 4
The most common gas in the troposphere is nitrogen.
I hope this helps!
Continental air masses are characterized by dry air near the surface while maritime air masses are moist .Polar air masses are characterized by cold air near the surface while tropical air masses are warm or hot. Arctic air masses are extremely cold.
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Answer:
An external stimuli is a stimulus that comes from outside an organism and causes a reaction.An internal stimuli is a stimulus that comes from inside an organism.
