Answer:
20.833 feet
Step-by-step explanation:
The light reflects off the mirror at the same angle that it hits it at.  So the triangle formed by the beam and mirror is similar to the triangle formed by Kevin and the mirror.
Therefore, we can write and solve a proportion.
h / 10 = 6.25 / 3
h = 20.833
The beam is 20.833 feet tall.
 
        
             
        
        
        
The fraction 13/25 is equivalent to 52 percent.
To workout this, divide the numerator by the denominator, sum this value to the integer part and multiply the result by 100%, so:
13/25 in percent = 13 ÷ 25 × 100% = 0.52 × 100% =  52%
        
                    
             
        
        
        
3 + 1.75m 
This represents 1.75 per mile plus a one time 3 charge. 
Another way this can be written is 
(1.75m + 6) - 3 
This is a less efficient way, but represents the same. It is 1.75 per mile, this is plus 6, therefore we add the -3 outside the parenthesis so it evens out to +3 as the base charge. 
Example: Lets say its 3 miles. 
3 + 1.75 (3) = 8.25 
(1.75 (3) + 6) - 3 = 8.25
 
        
                    
             
        
        
        
Answer:
Step-by-step explanation:
−4(−4u3−2+v2)
=(−4)(−4u3+−2+v2)
=(−4)(−4u3)+(−4)(−2)+(−4)(v2)
=16u3+8−4v2
=16u3−4v2+8