Bonjour,
1. Arteries carry blood from the heart to the rest of the body, whereas veins carry blood from the rest of the body back to the heart.
2. Almost all arteries carry oxygenated blood and almost all veins carry deoxygenated blood.
3. Arteries have a thick elastic muscle layer, whereas the muscle layer for veins is much thinner.
Eat worms from the ground
Answer:
b. Neither the researchers nor the study participants know who is receiving the drug and who is receiving the placebo.
Explanation:
In a double-blind test, there are two groups of participants: (1) people who are receiving the new drug and (2) people who are taking a placebo. Neither people from group (1) nor people from group (2) know what they are taking. Also, researchers recollect data from theses groups without knowing which person belongs to each group to avoid any "favoritism" caused by expected results.
