<prompt> Calculate Sensitivity and Specificity of ELISA in a population screened for HIV. Data is given below HIV Present HIV Absent ELISA ve 80 40 ELISA -ve 20 6060, 8080, 6066.6, 7575, 66.6  <response>: HIV Present HIV Absent ELISA ve 80 a 40 b ELISA -ve 20 c 60 d Sensitivity aac x 100 80100 X 100 80 Specificity d bd x 100 60100 X 100 60 PPV 80120 X 100 66 NPV 6080 X 100 75 