Answer:
C. But see the answer under C. Apparently C is the accepted answer.
Explanation:
A. Not A.I don't think that's a problem for gulls especially on beaches.
B. Not B.  Their feather do not look like they need much help in keeping their feathers attached when in flight.
C. This is not really the answer, but it is the best answer of these 4. The actual answer is that the bones are porous for better air intake which provides more oxygen and hence they are better able to fly.
D. Not D. Food has nothing to do with the problem. Birds get an adequate amount of food without their wings being porous. See the answer for C.
 
        
                    
             
        
        
        
Answer:
coccidioidomycosis
Explanation:
Valley fever is also referred as coccidioidomycosis. It is an acute infection caused by a fungi called coccidioides. The fungi present in the soil in a particular region. The spores of the fungi spread into air through wind, construction work or farming. Through breathing fungi reached to the lungs causing valley fever. The symptoms of coccidioidomycosis includes fever, pain in chest and coughing. Mild valley fever get cured in due course of time by itself but in severe cases antifungal medicines are prescribed by the physicians.  
 
        
             
        
        
        
Answer:
its the level of acid in substances
you put the amount of a item into a cup and add water.
Explanation:
 
        
             
        
        
        
According to the Big Bang theory, the universe was once very dense and is now expanding.