Answer: If a boa lays itself up next to you it is seeing if it can eat you without hurting itself...
 
        
                    
             
        
        
        
<span>carbohydrates ...................</span>
        
                    
             
        
        
        
Answer:
objective lenses
Explanation:
objective lenses with different magnifications, screwed into a circular "nosepiece" which may be rotated to select the required lens.
 
        
             
        
        
        
Answer:
Answer is B. Positive feedback regulation can generate an abrupt, all-or-none response in which the cell moves from ignoring a signal to responding to it very strongly.
Explanation:
Positive feedback  can be described as an example of feedback, which is a natural mechanism that amplifies the action of a system.
It can be better be explained further, as a situation whereby the blood pressure decreases and the response of the body also makes or causes the blood pressure to decrease the more.
Other examples of a positive feedback also include blood clotting, ripening of fruits , uterus muscle contraction, resulting to the stretching of the uterus during pregnancy.