About how long ago did the first single-celled life form appear on Earth? A. 130 million years ago
B. 1.5 billion years ago
C. 2.5 billion years ago
D. 4.1 billion years ago

Ture or false evidence for evolution includes millions of fossils

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.

What are characteristics of minerals? select 3 choices