Answer:
4t
Step-by-step explanation:
Let's form an equation here just to put it visually.
So it would be t+3*t
We can also write this as t+3t (If they're right next to eachother, it still indicates multiplication)
Now we can do t+3t which is 4t
If this doesn't make sense, then you can look at it this way
You do 1t+3t and since they're like terms, you can combine them and do 4t.
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. 
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Answer:
153.3852
Step-by-step explanation:
After the decimal, you count the places. 3 is in the ones place, 8 in the tenths, 5 in the hundreths, and 1 in the thousandths. The thousandths place is what we are rounding, so we look at the next number, 9, which tells us to round the 1 up to 2
Answer:
Step-by-step explanation:
d and e
Answer:
= n.
Step-by-step explanation:
Given : , b is any positive number not equal to 1 and n is any number.
To find : Evaluate the expression .
Formula used : 
. = y ∙ 
(x) and
![log_{b}(b) = 1.Solution : We have [tex]log_{b} b^{n}](https://tex.z-dn.net/?f=log_%7Bb%7D%28b%29%20%3D%201.%3C%2Fp%3E%3Cp%3ESolution%20%3A%20We%20have%20%20%5Btex%5Dlog_%7Bb%7D%20b%5E%7Bn%7D)
.
By logarithm rule : . = y ∙ (x).
Then = n∙ (b).
By logarithm rule : ![log_{b}(b) = 1.Now, n∙ [tex]log_{b}](https://tex.z-dn.net/?f=log_%7Bb%7D%28b%29%20%3D%201.%3C%2Fp%3E%3Cp%3ENow%2C%20n%E2%88%99%20%5Btex%5Dlog_%7Bb%7D)
(b) = n.
Therefore, = n.
