South America, Brazil, Canada, And Hawaii
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Answer:
Charles Darwin
Explanation:
Natural selection, most famously proposed by Charles Darwin, states that when presented with an environmental challenge, some individuals in a species will develop adaptations to face these challenges. Successful individuals will be more likely to mate and their offspring will inherit these adaptive traits, and will continue to pass for generations.
In this sense, plants face the challenge of the cold. Those that adapt to the cold will survive and reproduce, those that can't adapt to the cold will die. Eventually, only plants that can tolerate the cold will survive.
The approximate LD50 of the least toxic substance will be 130 mg/Kg.
- The dose necessary to cause the death of 50% of a population under test after a predetermined test period is known as the LD50 value for a drug.
- Commonly used as a broad indicator of a substance's acute toxicity are LD50 values.
- Greater toxicity is indicated by a lower LD50. A low LD50 of 500 mg/kg or less implies severe toxicity.
- Moderate toxicity is indicated by an LD50 of 500 to 1,000 mg/kg. A modest toxicity level of 1,000 to 2,000 mg/kg is indicated.
- The species is especially vulnerable to the poison if the LD50 is low. The lethal dose (LD50) of a specific poison might change significantly between several animal species.
- Thus out of all the options, LD50 130 mg/kg will have the lowest toxicity and 20 mg/kg will be the highest.
learn more about LD50 here: brainly.com/question/24845532
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