Answer:
B - Poor
Explanation:
As you get higher up, There is less oxygen which causes the engine to create less power.
Answer:
,
, ![\frac{dv}{dx} = -v_{in}\cdot \left(\frac{1}{L}\right) \cdot \left(\frac{v_{in}}{v_{out}}-1 \right) \cdot \left[1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}} -1 \right) \cdot x \right]^{-2}](https://tex.z-dn.net/?f=%5Cfrac%7Bdv%7D%7Bdx%7D%20%3D%20-v_%7Bin%7D%5Ccdot%20%5Cleft%28%5Cfrac%7B1%7D%7BL%7D%5Cright%29%20%5Ccdot%20%5Cleft%28%5Cfrac%7Bv_%7Bin%7D%7D%7Bv_%7Bout%7D%7D-1%20%20%5Cright%29%20%5Ccdot%20%5Cleft%5B1%20%2B%20%5Cleft%28%5Cfrac%7B1%7D%7BL%7D%5Cright%29%5Ccdot%20%5Cleft%28%5Cfrac%7Bv_%7Bin%7D%7D%7Bv_%7Bout%7D%7D%20-1%20%5Cright%29%20%5Ccdot%20x%20%5Cright%5D%5E%7B-2%7D)
Explanation:
Let suppose that fluid is incompressible and diffuser works at steady state. A diffuser reduces velocity at the expense of pressure, which can be modelled by using the Principle of Mass Conservation:
![\dot m_{in} - \dot m_{out} = 0](https://tex.z-dn.net/?f=%5Cdot%20m_%7Bin%7D%20-%20%5Cdot%20m_%7Bout%7D%20%3D%200)
![\dot m_{in} = \dot m_{out}](https://tex.z-dn.net/?f=%5Cdot%20m_%7Bin%7D%20%3D%20%5Cdot%20m_%7Bout%7D)
![\dot V_{in} = \dot V_{out}](https://tex.z-dn.net/?f=%5Cdot%20V_%7Bin%7D%20%3D%20%5Cdot%20V_%7Bout%7D)
![v_{in} \cdot A_{in} = v_{out}\cdot A_{out}](https://tex.z-dn.net/?f=v_%7Bin%7D%20%5Ccdot%20A_%7Bin%7D%20%3D%20v_%7Bout%7D%5Ccdot%20A_%7Bout%7D)
The following relation are found:
![\frac{v_{out}}{v_{in}} = \frac{A_{in}}{A_{out}}](https://tex.z-dn.net/?f=%5Cfrac%7Bv_%7Bout%7D%7D%7Bv_%7Bin%7D%7D%20%3D%20%5Cfrac%7BA_%7Bin%7D%7D%7BA_%7Bout%7D%7D)
The new relationship is determined by means of linear interpolation:
![A (x) = A_{in} +\frac{A_{out}-A_{in}}{L}\cdot x](https://tex.z-dn.net/?f=A%20%28x%29%20%3D%20A_%7Bin%7D%20%2B%5Cfrac%7BA_%7Bout%7D-A_%7Bin%7D%7D%7BL%7D%5Ccdot%20x)
![\frac{A(x)}{A_{in}} = 1 + \left(\frac{1}{L}\right)\cdot \left( \frac{A_{out}}{A_{in}}-1\right)\cdot x](https://tex.z-dn.net/?f=%5Cfrac%7BA%28x%29%7D%7BA_%7Bin%7D%7D%20%3D%201%20%2B%20%5Cleft%28%5Cfrac%7B1%7D%7BL%7D%5Cright%29%5Ccdot%20%5Cleft%28%20%5Cfrac%7BA_%7Bout%7D%7D%7BA_%7Bin%7D%7D-1%5Cright%29%5Ccdot%20x)
After some algebraic manipulation, the following for the velocity as a function of position is obtained hereafter:
![\frac{v_{in}}{v(x)} = 1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}}-1\right) \cdot x](https://tex.z-dn.net/?f=%5Cfrac%7Bv_%7Bin%7D%7D%7Bv%28x%29%7D%20%3D%201%20%2B%20%5Cleft%28%5Cfrac%7B1%7D%7BL%7D%5Cright%29%5Ccdot%20%5Cleft%28%5Cfrac%7Bv_%7Bin%7D%7D%7Bv_%7Bout%7D%7D-1%5Cright%29%20%5Ccdot%20x)
![v(x) = \frac{v_{in}}{1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}}-1 \right)\cdot x}](https://tex.z-dn.net/?f=v%28x%29%20%3D%20%5Cfrac%7Bv_%7Bin%7D%7D%7B1%20%2B%20%5Cleft%28%5Cfrac%7B1%7D%7BL%7D%5Cright%29%5Ccdot%20%5Cleft%28%5Cfrac%7Bv_%7Bin%7D%7D%7Bv_%7Bout%7D%7D-1%20%20%5Cright%29%5Ccdot%20x%7D)
![v (x) = v_{in}\cdot \left[1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}}-1 \right)\cdot x \right]^{-1}](https://tex.z-dn.net/?f=v%20%28x%29%20%3D%20v_%7Bin%7D%5Ccdot%20%5Cleft%5B1%20%2B%20%5Cleft%28%5Cfrac%7B1%7D%7BL%7D%5Cright%29%5Ccdot%20%5Cleft%28%5Cfrac%7Bv_%7Bin%7D%7D%7Bv_%7Bout%7D%7D-1%20%20%5Cright%29%5Ccdot%20x%20%5Cright%5D%5E%7B-1%7D)
The acceleration can be calculated by using the following derivative:
![a = v\cdot \frac{dv}{dx}](https://tex.z-dn.net/?f=a%20%3D%20v%5Ccdot%20%5Cfrac%7Bdv%7D%7Bdx%7D)
The derivative of the velocity in terms of position is:
![\frac{dv}{dx} = -v_{in}\cdot \left(\frac{1}{L}\right) \cdot \left(\frac{v_{in}}{v_{out}}-1 \right) \cdot \left[1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}} -1 \right) \cdot x \right]^{-2}](https://tex.z-dn.net/?f=%5Cfrac%7Bdv%7D%7Bdx%7D%20%3D%20-v_%7Bin%7D%5Ccdot%20%5Cleft%28%5Cfrac%7B1%7D%7BL%7D%5Cright%29%20%5Ccdot%20%5Cleft%28%5Cfrac%7Bv_%7Bin%7D%7D%7Bv_%7Bout%7D%7D-1%20%20%5Cright%29%20%5Ccdot%20%5Cleft%5B1%20%2B%20%5Cleft%28%5Cfrac%7B1%7D%7BL%7D%5Cright%29%5Ccdot%20%5Cleft%28%5Cfrac%7Bv_%7Bin%7D%7D%7Bv_%7Bout%7D%7D%20-1%20%5Cright%29%20%5Ccdot%20x%20%5Cright%5D%5E%7B-2%7D)
The expression for acceleration is derived by replacing each variable and simplifying the resultant formula.
The correct answer to this open question is the following.
The text structure of an article that discusses pharaohs and gives examples and explains how they look is a description.
The text structure called description allows the reader to fully know the characteristics of the people it is referring to, including some important details. That is why the author of a description text adds words like "such as" and "for example."
When describing something, the write is giving structure to the text and sequence. What comes first., what is followed, and so on.
That is why The text structure of an article that discusses pharaohs and gives examples and explains how they look is a description. It includes cause and effect sentences, and some comparisons in order to contrast an idea.