What percent of the water on earth is freshwater

Less than three percent of the world's water is freshwater. Most of this freshwater is locked up as solid ice that are inside of glaciers.

answer: node would be introduced.   is the correct

explanation:

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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