<h2>
Answer:</h2>
Removal of the tarnish from the silver is a <u>physical change</u>.
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Explanation:</h2>
The type of change which doesn't produce any new substance is called as physical change. Tarnish refers to the thin black layer that is formed on the silver. Formation of tarnish is chemical change as due to oxidation a black color layer is formed.
On the other hand, removal of tarnish from silver is considered as physical change as no new product is formed and only we are obtaining the silver in its pure form.
Answer:
C. Removing this step decreases the amount of carbon in the air: This is correct, removing factories would decrease the emission of greenhouse gases, thus decreasing CO2 in the atmosphere.
Explanation:
When we look at the picture we can see that the line that goes from G to C, goes from a factory to the atmosphere. As we know factories release a great number of elements into the atmosphere being one of them, carbon dioxide. Therefore taking into consideration we can proceed to analyze the following statements.
A. Removing this step prevents photosynthesis in the next step: This is not true industry increases carbon dioxide in the atmosphere, even if they don't exist there is enough CO2 for plants to perform photosynthesis.
B.Removing this step increases the amount of carbon in the soil: This is not true as factories release carbon dioxide to the atmosphere, not the soil.
C. Removing this step decreases the amount of carbon in the air: This is correct, removing factories would decrease the emission of greenhouse gases, thus decreasing CO2 in the atmosphere.
D. Removing this step increases carbon storage in plants: This is incorrect the carbon storage in plants is cording to their necessities independently of the abundance in CO2, in the atmosphere.
Answer:
The correct answer is- phosphorus and sulfur
Explanation:
Hershey and Chase used radioactive phosphorus and sulfur to label T2 bacteriophage. Then they infected E.coli with these bacteriophage labeled with radioactive phosphorus and sulfur.
After infection, they centrifuge the cell and found that radioactive phosphorus is present in the bottom and radioactive sulfur in supernatant . As sulfur is mostly the part of protein not DNA and is found in supernatant and phosphorus is mostly present in DNA not protein which was found in cell debris, therefore, it was proved that DNA is the genetic material.
