It should be fifteen to twenty percent of north american adults
Answer: Uncertainty
Explanation:
The principle of science used here is uncertainty. The various doctors attributed their sickness to hookworm gotten from cat and dogs but the uncertainty here is that it wasn't described they had access to the water because they were disappointed by the feces of dogs and cat found around, and how they all got the same rashes at the same time is questionable
Answer:
Here are ideas to keep in mind-----
Keep Your Neighborhood Clean. If you see trash on the ground, toss it in a trash can.
Recycle Cans, Bottles, and Paper. Save them at home and at school, and help your family recycle them.
Help Keep the Air Clean. Ride your bike or walk to school. ...
Save Paper. ...
Help Save Water.
The human heart works like a pump sending blood around your body to keep you alive. ... This blood delivers oxygen and nutrients to all parts of your body, and carries away unwanted carbon dioxide and waste products. Your heart and circulatory system works together to deliver blood to your organs so they can function.
