The answer to your question is 3.4
Because humans have five senses: feel, see, taste, hear, and smell. When you step on a nail you basically going to feel it and you brain can sense that and it can trigger nerves which can cause pain.
I agree with the taco person, D is most likely the correct answer!
CO2 from the blood is released from the blood cells into the alveoli for exhalation while O2 from the alveoli is received into the blood cells to deliver oxygen to other parts of the body
They can watch informal videos,take notes and participate in the class/ask questions.
