<span>~Hello there!
Your question: Sam came home from school with a cold caused by a virus and his sister, Ana, caught it from him. Sam got well and went back to school. A few days before Ana got well, Sam came down with a cold again. Their mother said that Ana had given the cold back to Sam. How likely is it that their mother is correct, and what does it mean for Ana's chances of
getting sick again?
Your answer: Acquired immunity, he must have picked picked up a different disease virus so Ana can get sick again.
The answer is option A.
Hope this helps~
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Answer: Gradualism (C)
Hope this helps
For the answer to the question above, I think the answer is simply because <span>four legs characteristic is not special to mammals but the hair that is something more important and special characteristic of the mammals, that's why. I hope this helps
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Valence is the number of electrons an atom must gain or lose in order to consummate its outer energy level or have a stable octet in its outer shell
