well it is not exactly essentioal but salmon need it
 
        
             
        
        
        
A cartoon strip is a grouping of some drawings which is trying to put forward a message or a story in a humorous way.
<u>Explanation:</u>
A cartoon strip is a grouping of drawings masterminded in interrelated boards to show brief silliness or structure a story, frequently serialized, with content in inflatables and subtitles.
A cartoon strip, arrangement of nearby drawn pictures, typically orchestrated on a level plane, that are intended to be perused as an account or a sequential succession. The story is normally unique right now. Words might be presented inside or approach each picture, or they might be shed out and out.
 
        
             
        
        
        
The double helix is a description of the molecular shape of a double-stranded DNA molecule. In 1953, Francis Crick and James Watson first described the molecular structure of DNA, which they called a "double helix," in the journal Nature.
        
             
        
        
        
Answer:
The dog breeder to check for all the details that meets her requirement of dogs. 
Explanation:
 A dog breeding is the practice of mating dogs. In the context, it is given that a dog breeder wants to purchase a male dog of three year old for her business and she founds an advertisement on the net about a purebred males that costs $700. Now before buying this purebred male dog, the dog breeder should first of all check whether the seller who is selling online is a licence breeder or not. 
The dog breeder should also check whether the dog is a purebred or not and should also find out the actual age of the dog. The health of the dog should be checked by an professional vet before buying the dog.