What should be applied to provide stability for an upper humerus injury?

In the metric system, the basic unit of length is the:

A. kilometer B. inch C. centigram D. meter

If using an image receptor holder with an external aiming device, the indicator ring attachment must be slid all the way down the metal arm of the device to be as close to the patient's skin as possible without touching the patient prior to the

exposure. Indicate whether the statement is true or false