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
Answer:
The electric bill of the Leonin family was of $ 877,626.
Step-by-step explanation:
Given that the Leonin family used 90 kWh for their electric consumption for the month of August, if the power consumption costs P9.7514 per kWh, to determine how much is their electric bill, the following calculation must be performed:
9.7514 x 90 = X
877.626 = X
Thus, the electric bill of the Leonin family was of $ 877.626.
The correct answer to this question is:
Diameter - B) a segment <span>between two points on a circle that passes through its center radius
</span>
Circumference - <span> F) the distance around a circle
</span><span>
Radius - </span><span>C) Circle A and a line segment connecting points B and C which are on the circle.
</span><span>
secant - </span><span>E) Circle A and a line segment connecting points B and C which are on the circle.
</span><span>
concentric circles - </span><span>D) Two circles that share the same center.
</span><span>
arc - </span><span>A) a piece of the circumference of a circle circumference.</span>