The answer to this question is -345.82
In a fraction it would be -17291/50
        
                    
             
        
        
        
Answer:

Step-by-step explanation:
we know that
30 and one-third miles is equal to

one-third of an hour is equal to

Applying proportion

Convert to mixed number

 
        
                    
             
        
        
        
Answer is 8
Work Shown:
f(x) = sqrt(5*x + 4)
f(12) = sqrt(5*12 + 4) ... replace every x with 12
f(12) = sqrt(60 + 4)
f(12) = sqrt( 64 )
f(12) = 8