<prompt> Pulse oximetry a Locates the isobestic point of hemoglobin and measure oxygen saturationb Is inaccurate in the presence of fetal hemoglobinc Is inaccurate in the presence of caboxyhemoglobind Measures oxygen contentabcacb  <response>: Pulse oximetry is used to determine :- i Hb concentration by isobetric points location, and ii Oxygen saturation But not oxygen content.Carboxy-hymoglobin can cause inaccurate reading but not the fetal hemoglobin. 