Answer: incomplete dominance
Explanation:
Incomplete dominance is also referred to as partial dominance or semi dominance. It occurs when the two forms of gene in a trait combine in such a way that one does not have a dominance over the other one. Therefore, there's a blend of both genes in the physical appearance of such organism.
Therefore, a low pitched male voices (RR) and a high pitched male voice (rr). Heterozygotes have a baritone voice is an example of incomplete dominance.
 
        
             
        
        
        
The statement is - True.
The humans, as advanced and developed they may be, can not function and survive without the proper functioning of the biosphere, hydrosphere, atmosphere, geosphere, cryosphere. All of those spheres are crucial in defining the life conditions on our planet, and the human kind, as all other living organisms, is heavily dependent upon them.
Unfortunately, the humans have been interfering a lot in the functioning of this systems, and make it harder and harder for them to function properly, and the interfering with the ecological systems is extremely dangerous as it can have a catastrophic consequences. 
 
        
                    
             
        
        
        
Answer:
D) Density of air and humidity levels
Explanation:
 
        
                    
             
        
        
        
Adaptive immunity is based upon the interactions between specific immune system cells and a specific antigen. This happens when cell surface of B cell binds to antigen thus lead to activating B cells. Hope this is the answer and this would help.