6. A ductile metal wire has resistance R. What will be the resistance of this wire in terms ofR if it is stretched to three times its original length, assuming that the density and resistivity of the material do not change when the wire is stretched? (Hint: The amount of metal does not change, so stretching out the wire will affect its cross-sectional area.) T. A person with body resistance between his hands of It] k accidentally grasps the terminals of a 14 lsf'vtur power supply. a} If the internal resistance of the power supply is 201313 , what is the current through the person' s body? b} What is the power dissipated in this body? c} If the power supply is to be made safe by increasing its internal resistance, what should the internal resistance be for the maximum current in the above situation to be 1.0!] 11191 or less