Answer:
(A)Show that the ratios StartFraction U V Over X Y EndFraction , StartFraction W U Over Z X EndFraction , and StartFraction W V Over Z Y EndFraction are equivalent.

Step-by-step explanation:
In Triangles WUV and XZY:

Therefore:

To show that the triangles are similar by the SSS similarity theorem, we have:

As a check:

The correct option is A.
Answer:
a) 
b)
c)
Step-by-step explanation:
Assuming the following question: Because of staffing decisions, managers of the Gibson-Marimont Hotel are interested in the variability in the number of rooms occupied per day during a particular season of the year. A sample of 20 days of operation shows a sample mean of 290 rooms occupied per day and a sample standard deviation of 30 rooms
Part a
For this case the best point of estimate for the population variance would be:

Part b
The confidence interval for the population variance is given by the following formula:
The degrees of freedom are given by:
Since the Confidence is 0.90 or 90%, the significance
and
, the critical values for this case are:
And replacing into the formula for the interval we got:
Part c
Now we just take square root on both sides of the interval and we got:
We have the equation:

We know two points and we will use them to calculate the parameters a and b.
The point (0,3) will let us know a, as b^0=1.

Now, we use the point (2, 108/25) to calcualte b:
![\begin{gathered} y=3\cdot b^x \\ \frac{108}{25}=3\cdot b^2 \\ 3\cdot b^2=\frac{108}{25} \\ b^2=\frac{108}{25\cdot3}=\frac{108}{3}\cdot\frac{1}{25}=\frac{36}{25} \\ b=\sqrt[]{\frac{36}{25}} \\ b=\frac{\sqrt[]{36}}{\sqrt[]{25}} \\ b=\frac{6}{5} \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20y%3D3%5Ccdot%20b%5Ex%20%5C%5C%20%5Cfrac%7B108%7D%7B25%7D%3D3%5Ccdot%20b%5E2%20%5C%5C%203%5Ccdot%20b%5E2%3D%5Cfrac%7B108%7D%7B25%7D%20%5C%5C%20b%5E2%3D%5Cfrac%7B108%7D%7B25%5Ccdot3%7D%3D%5Cfrac%7B108%7D%7B3%7D%5Ccdot%5Cfrac%7B1%7D%7B25%7D%3D%5Cfrac%7B36%7D%7B25%7D%20%5C%5C%20b%3D%5Csqrt%5B%5D%7B%5Cfrac%7B36%7D%7B25%7D%7D%20%5C%5C%20b%3D%5Cfrac%7B%5Csqrt%5B%5D%7B36%7D%7D%7B%5Csqrt%5B%5D%7B25%7D%7D%20%5C%5C%20b%3D%5Cfrac%7B6%7D%7B5%7D%20%5Cend%7Bgathered%7D)
Then, we can write the equation as: