What molecule has a r group

Cpr, or cardiopulmonary resuscitation, is a first-aid technique to save lives. it involves compressions of the patient's chest cavity. which description is the best description of the functions of chest compressions in cpr? chest compressions are done to pump the heart. chest compressions are done to strengthen the rib bones. chest compressions increase carbon dioxide inhalation. chest compressions allow the patient's muscles to wake up.

Moving down the ramp from 6 meters to

The earth formed roughly 4.5 billion years ago, yet evidence of life dates back to about 3.5 billion years ago. which one is not a possible hypothesis of how life on earth arose?