It's possible to estimate the percentage of fat in the body by measuring the resistance of the upper leg rather than the upper arm; the calculation is similar. A person's leg meas-ures 40 cm between the knee and the hip, with an average leg diameter (ignoring bone and other poorly conducting tissue) of 12 cm . A potential difference of 0.79 V causes a current of 1.6 mA . What are the fractions of muscle and fat in the leg?