Answer:
C. is unstable, with a short half life
Explanation:
Paracrine hormones are the hormones that act on neighboring cells only. These hormones or chemicals are largely unstable and have a brief life as do not visit the distantly placed target cells. For instance, somatostatin is secreted by D cells of the pancreas. It acts in a paracrine manner and inhibits the discharge of hormones from the neighboring beta and alpha cell. 
Likewise, one of the functions of unstable NO gas is to serve as a vasodilator. It is released by epithelium cells and serves to dilate arterioles and relax precapillary sphincters. Then it is degraded.
 
        
             
        
        
        
I think the correct answer from the choices listed above is option A. The anatomical adaptation which helps an elephant regulate its body temperature are its large ears increase surface area so that more heat is lost by radiation. Heat can be released as they flap these ears.  So there is your correct answer
        
                    
             
        
        
        
Seismic waves help scientists understand Earth's layers by:
- Scientists can observe how seismic waves change speeds when passing through different layers.
- Scientists can observe which seismic waves cannot pass through certain layers.
<h3>What are Seismic waves?</h3>
These are waves which are generated as a result of the movement of 
materials in the earth. They change speed as a result of the collision with 
materials in the earth and know the types of material present as a result of 
some types not being able to pass through certain medium.
Read more about Seismic waves here brainly.com/question/8553835
 
        
             
        
        
        
Answer:
Adding organic matter or growing cover crops
Explanation:
Adding organic matter or growing cover crops  in the form of aged manure to the soil is a process used in producing garden soil and this is because not only will the compost make the land good and fertile it will also makes the garden soil friable unlike the application of fertilizer 
 
        
             
        
        
        
Answer:
You're right its C. There will be no transfer of heat from the nickel to the water in the glass.
I hope this answers your question(s). Have a good weekend! 
:)