<prompt> In mid clavicular plane, lower border of lung lies at level of:4th rib6th rib8th rib10th rib  <response>: The lower border of the lung in midinspiration follows a curving line, which crosses the 6th rib in the midclavicular line and the 8th rib in the midaxillary line, and reaches the 10th rib adjacent to the veebral column posteriorly. 