Answer:
the differnt dna and rna strucures in the mammals cause differen tlooks they have also evolved from being in the wilf most of their lives
Explanation:
 
        
             
        
        
        
The first top one is right
        
             
        
        
        
All the members of a specific species that live in an area are a population.
        
             
        
        
        
Answer:
Celestial microwave radiation found a strange microwave signal causing background noise in the radio telescope. The signal came from every direction. The young universe would have been very hot. The microwave background radiation is the remaining heat from the Big bang. 
I tried my hardest and this is what I put on MY test so good luck
 
        
             
        
        
        
Relative dating concerns the dating of fossils by using stratum (layers in the rock) to find the estimated age.
Absolute dating is finding the age of a fossil by using radiometric methods, such as fluorine dating or half-life dating; which is more accurate than relative dating.