Answer:
The answer is B 
Explanation:
got it right on unit test review
 
        
             
        
        
        
1. I think that rock from the mantle is added to the edges of both plates at convergent plate boundaries.
2. I think that one plate sinks into the mantle and is destroyed at divergent boundaries.
 
        
             
        
        
        
Answer:
D) The fungicide will reduce the stability of the ecosystem because nutrients in the soil will be less likely to be recycled, directly impacting plant nutrition and growth.
Explanation:
Fungicide are primarily applied to an area to kill off fungi species in that place. 
Fungi are very important groups of organisms. They are natural "recyclers". 
In a food chain or web they can be classified as decomposers. 
Decomposers are organisms that takes feeds on dead and decaying organic matter. 
The produce useful materials and releases nutrients from life back into nature. 
Killing them off by applying fungicides is a damaging act to their sustenance. 
Without decomposers such as fungi, the ecosystem becomes less stable  and soil nutrients will not be properly recycled. 
 
        
                    
             
        
        
        
Answer:
B. Use the polymerase chain reaction (PCR) to make multiple copies of the DNA.
Explanation:
The scientist is to analyze a small sample of DNA, the most useful step to start this would be first the use of polymerase chain reaction to make various copies of that DNA sample. PCR is essential and quick process that gives a lot of copies within few hours. It uses the sample or target DNA, according to which the primers are designed. Taq polymerase and DNA polymerase are also used in the process, it consist of various cycles in which copies are made. There are three basic steps 'Denaturation', 'annealing', and 'extension'.