Vertebrates do not have an exoskeleton they have backbones
        
             
        
        
        
Answer:
The correct answer is "The common ancestor of coyotes and domestic dogs is more recent than the common ancestor of red foxes and domestic dogs".
Explanation:
One of the fastest way to known if two species have recent common ancestors is to look if they have common taxonomic ranks. In this case we can conclude that The common ancestor of coyotes and domestic dogs is more recent than the common ancestor of red foxes and domestic dogs, because the coyotes (Canis latrans) and the domestic dogs (Canis familiaris) share the same genus (Canis). The common ancestor of foxes and domestic dogs is more ancient because red foxes (Vulpes fulva) do not share the same genus has domestic dogs (Canis familiaris).
 
        
             
        
        
        
Sean, who weighs the least of the three, will have the highest blood alcohol concentration (BAC). 
The less a person weighs, the more they will be affected by a given amount of alcohol. People of the same weight, even the same gender, individuals with a lower percentage of body fat will have lower blood alcohol concentration than those with a higher percentage of body fat.
Hope this helps! :)
        
             
        
        
        
The provided question is incomplete, the correct and complete question is as follows:
Choose the answer that best completes the sentence below.
Scientists group materials together ____________ it is easier to compare and study them that way.
A however
B but
C although
D because 
Answer:
The correct answer is - option D because.
Explanation:
Researcher and scientists tries to group material together on their similarities and difference to one another which makes it easier to study and compare various type of materials.
It is the one of major reasons to differentiate materials between groups like liquids state, gases state,  plasma state and solid state materials. One can easily see the difference and comparison is very clear on this type of grouping of materials.
Thus, the correct answer is - option D.
 
        
             
        
        
        
Answer:
that means they are not a prey to any animal