Where is the CR centered for an AP projection of the knee?

How and where should the CR be directed for the AP axial projection of the cervical vertebral column?

At which level on the plantar surface should the CR enter the foot for the axial (plantodorsal) projection of the calcaneus?

Which projection of the proximal shoulder is used for trauma?

Why is the PA rather than the AP projection recommended for a small bowel series?

When positioning the mortise oblique projection of the ankle, the extremity needs to be rotated:    

What is the purpose of elevating the chin for PA erect chest radiographs?

A patient is in the intensive care unit with multiple injuries. The attending physician is concerned about a pleural effusion in the left lung.  The patient had surgery recently and cannot stand.  Which position/projection would be best to rule out pleural effusion?

How many electrodes should a medical assistant apply to a patient for a 12-lead EKG?

Where is the central ray centered for an AP projection-external rotation of the shoulder?