Answer:
PVR is calculated by the formulae: 
Explanation:
Pulmonary vascular resistance may be defined as the resistance to blood through the pulmonary circulation.
PVR can be determined by the following formula:

Here, PAP is the pulmonary artery pressure, PAOP is pulmonary artery occlusion pressure and CO is cardiac output.
I think it brings to the warm places cold air and to cold places it brings warm air
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