When the heated part of the mantle rises through the cooler part , this is an example of Convection.
Hypothesis are testable meaning you are able to preform an experiment to see the relationship between two variables.
Diffusion is one form of passive transport that doesn't require the expenditure of cellular energy. A molecule can diffuse passively through the cell membrane if it's lipid-soluble, uncharged, and very small, or if a carrier molecule can assist it. ... The assisted process is known as facilitated diffusion.
Got this off google but still hope it helps :)
Answer:
Unequal heating of the earth
Explanation:
Warm air rises at the equator and moves towards the poles. At the poles, the cooler air sinks and moves back to toward the equator