The water table is:
the surface of ground water
only found underground
usually very shallow
all of the above

Ground Water

Explanation:

The surface of this ground water is called the water table. In lakes and swamps, the water table is above the surface of the ground. In other areas the water table may be a few meters or even hundreds of meters beneath the surface.

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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format change of dna.