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What is thought to have caused the mass extinction at the end of the cretaceous period?

When in solution, a molecule that moves slowly across an artificial membrane moves rapidly across a plasma membrane. this molecule rapidly enters the cell regardless of whether its concentration is higher inside or outside the cell. using this information, which transport mechanism is most likely to be responsible for the movement of the molecule across a plasma membrane? view available hint(s)when in solution, a molecule that moves slowly across an artificial membrane moves rapidly across a plasma membrane. this molecule rapidly enters the cell regardless of whether its concentration is higher inside or outside the cell. using this information, which transport mechanism is most likely to be responsible for the movement of the molecule across a plasma membrane? active transportexocytosis

When a gasoline engine burns gasoline, what type of chemical reaction is occurring?