Answer: Alligators living in a pond is an example of natural habitats
Answer: alternative A.
Explanation: In this case, we will consider people that already have had a heart attack. In this specific group of 1,000 people, 236 exercised regularly and had gone through this situation.
We can infer that 23.6% of people who exercised regularly have experienced that by dividing 236/1,000= 0.236= 23.6%.
If 236 people exercised, 1,000-236=764 didn't exercise regularly prior to their heart attacks, so 74.6% were considered to be sedentary.
If there's 0.236 chance out of 1 to exercise and still have a heart attack compared to 0.764 out of 1 to be sedentary and have the same experience, we can divide both ratios to compare them, so 0.236/0.764= 0.3089.
Alternative A claims that people who exercise have around 0.5 chance of having heart attacks compared to people who don't. Since our ratio resulted in 0.3089, we consider this number the closest to 0.5. Alternative <u>B is absurd because in order for people who exercise to have 2x the risk compared to people who don't, the number of people who exercised and went through that must be 2x bigger than people who didn't</u>. Alternative <u>C doesn't apply as well, because we already verified that the chance people who exercise have a heart attack equal to 23,6%. </u>
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The answer is Vaccination.
Acquired or adaptive immunity is the body's third line of defense. This is protection against specific types of pathogens. Acquired immunity may be either natural or artificial in nature. Both natural and artificial immunity have passive and active components. Active immunity results from an infection or an immunization, while passive immunity comes from naturally or artificially gaining antibodies.
A desert is a hot wasteland covered with sand and a tundra is a frozen wasteland covered in ice
