Answer:
Because flu viruses evolve so quickly, last year's vaccine may not protect you from this year's viruses. New flu vaccines are released every year to keep up with rapidly adapting flu viruses.
Answer: Your best answer is <u>A. regulates breathing and heart rate</u>
Hope this helps!
It actually says about the theory of evolution !!! as in what sequence they comes and become extinct !!! So B
A polar molecule has a positive and negative end because of electronegativity.
Answer: A
Why? All the other options you can really control that you do that, you usually shiver br side your body NEEDS to warm up not wants to. So you shiver to hit equilibrium.
Hope this helps :D
