It is 19 because of the Pythagorean theorem which states a squared plus b squared is c squared.
        
                    
             
        
        
        
The number that is not irrational is  . The correct option is the second option
. The correct option is the second option 
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Irrational numbers </h3>
From the question, we are to determine which of the given options is not irrational 
Irrational numbers are the set of real numbers that cannot be expressed in the form of a fraction, p/q, where p and q are integers. 
 is a repeating decimal and it can be expressed as a fraction
  is a repeating decimal and it can be expressed as a fraction

∴  is not an irrational number. It is a rational number
 is not an irrational number. It is a rational number
The other options cannot the expressed as a fraction.
Hence, the number that is not irrational is  . The correct option is the second option
. The correct option is the second option 
Learn more on Irrational numbers here: brainly.com/question/11919233
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