The <em>total</em> area of all six faces of the tunnel is 
square centimeters.
<h2>Procedure - Surface area of a tunnel for a toy train</h2>
The surface area of the solid (
) used to represent the tunnel for a toy train is the sum of its six faces (two <em>semicircular</em> sections, inner <em>semicircular</em> arc section, outer <em>semicircular</em> arc section, two rectangles).
<h3>Determination of the surface area of the tunnel based on information of the diagram</h3>
We calculate the surface area as following:
![A = 2\cdot \frac{\pi}{2} \cdot [(10\,cm)^{2}-(8\,cm)^{2}] + \pi\cdot (8\,cm)\cdot (30\,cm) + \pi\cdot (10\,cm)\cdot (30\,cm) + 2\cdot (2\,cm)\cdot (30\,cm)](https://tex.z-dn.net/?f=A%20%3D%202%5Ccdot%20%5Cfrac%7B%5Cpi%7D%7B2%7D%20%5Ccdot%20%5B%2810%5C%2Ccm%29%5E%7B2%7D-%288%5C%2Ccm%29%5E%7B2%7D%5D%20%2B%20%5Cpi%5Ccdot%20%288%5C%2Ccm%29%5Ccdot%20%2830%5C%2Ccm%29%20%2B%20%5Cpi%5Ccdot%20%2810%5C%2Ccm%29%5Ccdot%20%2830%5C%2Ccm%29%20%2B%202%5Ccdot%20%282%5C%2Ccm%29%5Ccdot%20%2830%5C%2Ccm%29)
The <em>total</em> area of all six faces of the tunnel is square centimeters. 
To learn more on surface areas, we kindly invite to check this verified question: brainly.com/question/2835293
He just switched sides of the variables and numbers. Instead if adding the opposite.
The answer is $2,250. (D). To get the answer you do 2,499-249= 2,250. Hope this helps!!
Answer:
![\frac{\sqrt[4]{3x^2} }{2y}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Csqrt%5B4%5D%7B3x%5E2%7D%20%7D%7B2y%7D)
Step-by-step explanation:
We can simplify the expression under the root first.
Remember to use 
Thus, we have:
![\sqrt[4]{\frac{24x^{6}y}{128x^{4}y^{5}}} \\=\sqrt[4]{\frac{3x^{2}}{16y^{4}}}](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7B%5Cfrac%7B24x%5E%7B6%7Dy%7D%7B128x%5E%7B4%7Dy%5E%7B5%7D%7D%7D%20%5C%5C%3D%5Csqrt%5B4%5D%7B%5Cfrac%7B3x%5E%7B2%7D%7D%7B16y%5E%7B4%7D%7D%7D)
We know 4th root can be written as "to the power 1/4th". Then we can use the property 
<em>So we have:</em>
<em>![\sqrt[4]{\frac{3x^{2}}{16y^{4}}} \\=(\frac{3x^{2}}{16y^{4}})^{\frac{1}{4}}\\=\frac{3^{\frac{1}{4}}x^{\frac{1}{2}}}{2y}\\=\frac{\sqrt[4]{3x^2} }{2y}](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7B%5Cfrac%7B3x%5E%7B2%7D%7D%7B16y%5E%7B4%7D%7D%7D%20%5C%5C%3D%28%5Cfrac%7B3x%5E%7B2%7D%7D%7B16y%5E%7B4%7D%7D%29%5E%7B%5Cfrac%7B1%7D%7B4%7D%7D%5C%5C%3D%5Cfrac%7B3%5E%7B%5Cfrac%7B1%7D%7B4%7D%7Dx%5E%7B%5Cfrac%7B1%7D%7B2%7D%7D%7D%7B2y%7D%5C%5C%3D%5Cfrac%7B%5Csqrt%5B4%5D%7B3x%5E2%7D%20%7D%7B2y%7D)
</em>
<em />
<em>Option D is right.</em>
