Answer: Resources such as rocks, soil, water, and air, nonliving things that help to meet our needs. You learn that water and air are renewable resources that can be replaced quickly. You learn that soil and rocks are non-renewable and cannot be replaced quickly. Comment Below if this helped! Brainliest Would be amazing!
B. Mainly humid-continental with cool summers.
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Answer:
The correct answer is b. He determined that DNA contains four nitrogenous bases.
Explanation:
Levene was an American biochemist who studied the structure of DNA in the early 1900s and in 1920 he found that DNA consists of four nitrogenous bases that are Adenine, Guanine, Thymine, Cytosine.
He also found deoxyribose sugar and phosphate group and said that nucleotide is the basic unit of DNA which contains a ribose sugar with attached nitrogenous base and phosphate group.
He also concludes that an equal amount of adenine, guanine, thymine, and cytosine makes the DNA which is now known as tetranucleotide hypothesis. So the correct answer is b. He determined that DNA contains four nitrogenous bases.
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