The last cartilage ring on the trachea before it bifurcates into the right and left primary bronchi is known as the:

Megaloblastic anemias are caused by a defect in the synthesis of:

a. Deoxyribonucleic acid (DNA) b. Ribonucleic acid (RNA) c. Erythropoietin d. Heme

For an AP lumbar projection, the

1. ASISs are positioned at equal distances from the imaging table. 2. patient's legs are extended. 3. long axis of the vertebral column is aligned with the short axis of the collimated field. 4. central ray is centered to the iliac crest when a 14- ? 17-inch (35- ? 43-cm) IR is used. a. 1 and 4 only b. 2 only c. 1, 2, and 4 only d. 1, 2, 3, and 4