Question

The flat bone forming the anterior part of the thoracic cavity that is used for hand placement in CPR

Answer 1

Structure.

The sternum is a long, flat bone, forming the middle portion of the front of the chest. The top of the sternum supports the clavicles (collarbones) and its edges join with the costal cartilages of the first two pairs of ribs.
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Answer 2

Sternum

Step-by-step explanation:

Structure. The sternum is a long, flat bone, forming the middle portion of the front of the chest. The top of the sternum supports the clavicles (collarbones) and its edges join with the costal cartilages of the first two pairs of ribs.