<span>The answer is A. Roast Beef because all ground meat, injected, or marinated meats must be cooked to 155 degrees to kill any microorganisms that may cause sickness. Roast Beef is a marinated or 'flavor injected' meat therefore it requires the 15 seconds of 155 degree temperature reading.</span>
        
             
        
        
        
Answer:
i believe the answers are A) geyser  and c)25%
Explanation:
 
        
             
        
        
        
A geologist studies rocks and such
        
             
        
        
        
Answer:
A. Soot and dust is released into the air from the smokestack of a
power plant.
 
        
                    
             
        
        
        
Hi,
Harshey and Chase did a great experimentation which was basically a two step experiment to prove that DNA and not proteins are the actual carriers of genetic information from parents to offspring.
- In the first part of their experiment, they used bacteriophages (virus that eat bacteria). They used radioactively labeled sulphur(35S) medium to grow bacteriophages and observed that all the bacteriophages had proteins with radioactive sulphur(35S).
- In the next step they allowed these phages to infect bacteria and to their surprise, they found that the bacteria did not had radioactively labeled sulphur in them because the coat of bacteriophage stays outside the body of bacteria when it attacks it. This proved that DNA not proteins were the hereditary material.
- To make their results more reliable, they did a second experimentation in which, they marked the DNA of the phage with radioactive phosphorus 32P. After labeling DNA, they repeated the same experiment and this time, they found radioactive phosphorus inside the bacteria. 
<em>This meant that the bacteria had DNA of phage entered inside them and this again proved that DNA not proteins are the hereditary material. You can see attached image for better understanding.
</em>
Hope it help!