Spontaneous generation was a (refuted) theory that some forms of life can arise from inorganic matter.
Louis Pasteur refuted it in a series of experiments, in which he boiled different matter (grape juice, broth) which would kill all the bacteria and let it stay for a long time to see if it would develop life (he also had a control condition in which he let the boiled liquid interact with the outside words, and those would develop bacterial life).
Acid rain<span> is caused by a </span>chemical<span> reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other </span>chemicals<span> to form more </span>acidic<span> pollutants, known as </span>acid rain<span>.</span>
1/2 of a radioactive substance will remain after 3 half lives.
Answer:
Conditioned stimulus
Explanation:
The conditioned stimulus is a previously neutral stimulus that, after becoming associated with the unconditioned stimulus, eventually comes to trigger a conditioned response.