Answer:
15 seconds
Step-by-step explanation:
Because the split id 25% and 75%, we could create another average pretending that there are four kids, one who ran in 12 seconds, and three who ran in 16.
Equation for averages: (a₁ + a₂ + a₃ + ...  )/ n
)/ n
Plug in:<em> (12 + 16 + 16 + 16)/4</em>
Add: 60/4
Divide: 15 seconds
 
        
             
        
        
        
I got it =4/5 hope it’s right
 
        
        
        
Answer:  d. $852.96
Step-by-step explanation:
Given: The net pay = $667.17
Since net pay is the amount of money your employees take home after all deductions have been taken out.
We know that gross pay is the amount of money that employees receive before any taxes and deductions are taken out. 
Thus to find the gross pay, we need to add all of the deductions to the net pay as:
Gross pay
Hence, D is the right option. 
 
        
                    
             
        
        
        
Answer:

Step-by-step explanation:
By applying the concept of calculus;
the moment of inertia of the lamina about one corner  is:
 is:

where :
(a and b are the length and the breath of the rectangle respectively )


![I_{corner} =  \rho [\frac{bx^3}{3}+ \frac{b^3x}{3}]^ {^ a} _{_0}](https://tex.z-dn.net/?f=I_%7Bcorner%7D%20%3D%20%20%5Crho%20%5B%5Cfrac%7Bbx%5E3%7D%7B3%7D%2B%20%5Cfrac%7Bb%5E3x%7D%7B3%7D%5D%5E%20%7B%5E%20a%7D%20_%7B_0%7D)
![I_{corner} =  \rho [\frac{a^3b}{3}+ \frac{ab^3}{3}]](https://tex.z-dn.net/?f=I_%7Bcorner%7D%20%3D%20%20%5Crho%20%5B%5Cfrac%7Ba%5E3b%7D%7B3%7D%2B%20%5Cfrac%7Bab%5E3%7D%7B3%7D%5D)

Thus; the moment of inertia of the lamina about one corner is 
 
        
             
        
        
        
Question a:
Mass = Density × Volume 
Density = Mass/Volume
Volume of the tree trunk (the shape of Cylinder) = Area of circular base × height
Volume = [πr²] × h
Volume = [π × 0.25²] × 20
Volume = 3.93 m³
Density = 380 kg/m³
Mass = Density × Volume
Mass = 380 × 3.93
Mass = 1493.4 kg
------------------------------------------------------------------------------------------------------------
Question b)
The growth ring = 4 millimeters = 4÷1000 = 0.004
New diameter = 0.5 + 0.004 = 0.5004
New height = 20 + 0.2 = 20.2
New volume = [πr²] × h
New volume = [π × 0.2502²] × 20.2
New volume = 3.97 m³