The Cretaceous–Paleogene (K–Pg) extinction event (also known as the Cretaceous–Tertiary (K–T) extinction) was a sudden mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million years ago.
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Answer: B. Comparative embryology
Explanation: Good luck! :D
Answer:
A. Chemical modification may allow for extended drug capacities such as expanded spectrum of activity and increased stability.
Explanation:
Any modification in antibiotic structure and chemical will affects its ability in a way to increase it capability of target microbes and act efficiently. These modification can increase half life and stability of the drug.
