For the squid axon, the typical values for the intracellular and extracellular concentrations for the major ion species, and their permeability coefficients at room temperature (20C) are given below. (a) Calculate the equilibrium resting potential. (b) Suppose the external potassium is increased by a factor of 10. What is the new value of the equilibrium potential for potassium EK? (c) During the absolute refractory period of an action potential, sodium permeability increases by a factor of 1000. What is the new transmembrane potential? Species Intracellular Extracellular Conc. (mM) Conc. (mM) Permeability (cm/s) K+ 400 10 2 x 10-6 Na + 50 440 2 x 10-8 CI- 40 560 4 x 10-6