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Answer:</h2>
The Mesozoic era is featured by the arousal of <u>b. birds</u>.
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Explanation:</h2>
The Mesozoic Time is the age of the dinosaurs and kept going nearly 180 million a long time from around 250 to 65 million a long time back. It includes periods called the Triassic, Cretaceous, and Jurassic periods. A mass-extinction stamped the starting and conclusion of the Mesozoic Period. The occasion that caused the move from the Paleozoic time to the Mesozoic period was the most prominent termination this soil has seen.  
There's noteworthy prove that birds developed inside theropod dinosaurs, particularly, that winged creatures are individuals of Maniraptora, a category which belongs to dinosaurs period.
 
        
        
        
<span>The appropriate answer is c. sonar. Oceanographers use sonar to determine the ocean depth. A sonar signal is sent from the ship. Oceanographers record the time taken for the signal to leave the ship and for it to return. Knowing the speed of sound in water, they are able to calculate the depth of the water. This method is also used to generate bathymetric images of the ocean floor. </span>
        
                    
             
        
        
        
Muscles and organs derive the most benefit from the blood that flows in the arteries and capillaries because they obtain food substances and oxygen while releasing wastes.
        
                    
             
        
        
        
Answer:
Exposure to a virus is closely related to the development of immunity, since the immune system is responsible for creating antibodies in response to the presence of potentially harmful biological agents, such as these viruses.
Explanation:
Viruses are biological agents that can produce diseases when they enter the body of a living being.<u> In response to contact with a virus, the</u><u> immune system</u><u> synthesizes specific </u><u>antibodies</u> to combat the foreign biological agent.
Antibody immunity can be of two types. It is fast when it is mediated by immunoglobulins M (IgM), which attack the virus anywhere, while the late and prolonged response is due to the development of immunoglobulins G (IgG).
An example of immunity to a virus occurs with the exhibition to the virus of the Dengue, that creates permanent immunity to the viral serotype to which an individual is exposed.
The acquired immunity, mediated by antibodies, is the base for the development of vaccines.
 
        
             
        
        
        
I think d is the correct answer or not