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marysya [2.9K]
3 years ago
7

A) How long will it take for 40.0 grams of Radium-226 (Ra-226) to decay to leave a total of 2.5 grams of Ra-226? Ra-226 has a ha

lf-life of 1600 years.
B) If there are 80.0 grams of Neptunium-240 (Np-240), how much Neptunium-240 will remain after 4 hours? The half-life of Neptunium-24 is 1 hour.
Biology
2 answers:
kumpel [21]3 years ago
8 0

Answer:

a) 6400 years

b) 5 grams

Explanation:

a) to get 6400 years, the 40 grams is halved 4 times to get to 2.5g and 4 times 1600 is 6400

b) 80 is halved 4 times and the final result you get is 5 grams

80/2= 40/2= 20/2=10/2=5

each divided by 2 represents 1 hour

sergey [27]3 years ago
4 0

Answer:

[ A ] 6400 years

[ B ] 5 grams

Explanation:

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Answer:

Hyperimmunoglobulinemia E Syndrome

Explanation:

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How do derived characteristics affect cladograms?
Inessa [10]

Answer:

The Impact of Evolution

Darwin changed everything. The publication of his work on The Origin of Species in 1859, threw the whole of biological science into a new paradigm, including the study of classification theory and the principles of taxonomy.

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This was acceptable because (a) no one could think of anything better, and (b) most people at the time believed in the 'fixed species' concept in which organism had been created in their current form and could never change.

After Darwin it was realized that organisms could indeed change, and that all current forms of living things had arrived at that form by change and natural selection, the mechanism of evolution. Scientists began to construct phylogenies, lists or diagrams that showed the evolutionary paths taken by populations of organisms through many generations and over long periods of time.

These phylogenetic diagrams quickly started to look like trees, as it was realized that ancestral stocks occasionally broke up, branched and became two or more different species, which could later branch again and again. A phylogenetic tree was a bit like a family tree, showing who the nearest relatives were and who shared a common ancestor, and when.

Organisms were related to one another, and these relationships could form the basis of a new type of taxonomy; on based on evolutionary origin and evolutionary relatedness.

Explanation:

The Impact of Evolution

Darwin changed everything. The publication of his work on The Origin of Species in 1859, threw the whole of biological science into a new paradigm, including the study of classification theory and the principles of taxonomy.

While using logic as the basis of their work, both Aristotle and Linnaeus had developed their classification schemes on taxonomic principles that were fundamentally arbitrary. Their groups, while logical, were not based on any obvious relationships of a biological nature. They were convenient groups that humans could quickly see, identify and use.

This was acceptable because (a) no one could think of anything better, and (b) most people at the time believed in the 'fixed species' concept in which organism had been created in their current form and could never change.

After Darwin it was realized that organisms could indeed change, and that all current forms of living things had arrived at that form by change and natural selection, the mechanism of evolution. Scientists began to construct phylogenies, lists or diagrams that showed the evolutionary paths taken by populations of organisms through many generations and over long periods of time.

These phylogenetic diagrams quickly started to look like trees, as it was realized that ancestral stocks occasionally broke up, branched and became two or more different species, which could later branch again and again. A phylogenetic tree was a bit like a family tree, showing who the nearest relatives were and who shared a common ancestor, and when.

Organisms were related to one another, and these relationships could form the basis of a new type of taxonomy; on based on evolutionary origin and evolutionary relatedness.

7 0
4 years ago
Explain the consequences of an increase of two degrees Fahrenheit.
kenny6666 [7]

Answer:I think it was The Heat waves can be dangerous, causing illnesses such as heat cramps and heat stroke, or even death. Warmer temperatures can also lead to a chain reaction of other changes around the world. That's because increasing air temperature also affects the oceans, weather patterns, snow and ice, and plants and animals

Explanation:

hope this helps have a nice night ❤️❤️❤️

4 0
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aalyn [17]

Answer:

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Explanation:

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