1. marine scientists get information about aquatic populations from which of the following sources?
- news reports
- helicopter pilots
- commercial fishermen
- individuals on the beach

2. countershading is an example of
- a trait unique to sharks
- a technique used for hunting
- an adaption to the environment
- the issue created by light in the ocean

3. phytoplankton is the first link in the food chain.
- true
- false

Which conditions are necessary for natural selection to occur? select all of the answers that apply. a. inheritable adaptations vary among individuals. b. the population size is increasing. c. more individuals are born than can survive. d. fitness varies among individuals. e. the environment changes suddenly and drastically.

Solutions to environmental problems in europe must

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.