21. Which is the best example of an ecologist studying population density? a. The number of rhinos per square kilometer
b. The number of rhinos in a herd.
C. The number of rhinos on the planet.
d. The number of rhinos bom each year.

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.