What is the direct cause of most earthquakes? O Gravitational pull on bedrock by the moon
O deposition of sediment in lakes and oceans
O movement of bedrock along a fault line
O heat exchange betwęen the crust and the atmosphere

Pretty sure it's C or B? Most likely C.

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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