<span>In an event of a rattlesnake bite, keeping the person bitten to calm down is the 1st thing to do. When the venom reaches the heart of the victim, it could lead to a fatal death. So by calming down, the circulation of blood is prevented to rise. After which, they directly cut an "x" at the middle of the bite marks and suck out blood as many as possible hoping that the venom is also sucked out too. This was an old technique used in the Oregon trail and may not be the best technique there is nowadays.
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700,000 infected each year in the united states
The answer is D because everyone benefits from physical activity.
Answer: the heart, the blood vessel, and the blood itself
Explanation: hope this helps