This is at around negative 90 millivolts. Now, before we discuss anything else, let's discuss the relative concentrations of four different ions found on the inside and on the outside of the membrane. So when the cell is resting, when it's not generating any action potential, that is, when we are at phase four, these are the relative concentrations. So we have a higher concentration of sodium, calcium and chloride on the outside than on the inside portion of the cell. And we have a lower concentration of potassium on the outside than on the inside. And these are the relative concentrations given to us in millimolar.