I think B. I hope this helps.
Answer:
Shape of Red Blood Cells Erythrocytes are biconcave discs with very shallow centers. This shape optimizes the ratio of surface area to volume, facilitating gas exchange. It also enables them to fold up as they move through narrow blood vessels.
Answer: The FDA and USDA cerate food safety programs, safeguards to protect Americans, to protect people from unsafe food. The FDA has monitoring programs for pathogens, naturaltoxins, pesticides, etc.; their methods are science-based.
Answer:B, D
Explanation:
When the roller coaster starts flying down the hill, it gains kinetic energy and loses potential energy.