I believe for number 1 the answer is A 260
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Answer:</h2>
<h3>1. Hepatitis B </h3><h3>2. Levels of circulating antibodies against a certain antigen.</h3>
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Explanation:</h2>
<h3>Hope its help</h3>
I think that it is the bone system please tell me if right
the three types of symbiosis are: mutualism, commensalism, and parasitism. Parasitism is when one is helped one is harmed, commensalism is when one is helped and one isn't bothered, and mutualism is when all organisms are benefited. Did I help?