Answer:
In an observational study, we measure or survey members of a sample without trying to affect them. In a controlled experiment, we assign people or things to groups and apply some treatment to one of the groups, while the other group does not receive the treatment.
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Applying the rules, it is found that ordered pair (24,6), option A, works for both rules.
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The rule 1 is that y is x divided by 4, that is:
![y_1 = \frac{x}{4}](https://tex.z-dn.net/?f=y_1%20%3D%20%5Cfrac%7Bx%7D%7B4%7D)
The rule 2 is that y is x subtracted from 18, that is:
![y_2 = x - 18](https://tex.z-dn.net/?f=y_2%20%3D%20x%20-%2018)
In item A, we have that the input x = 24, thus, the results of the expressions are:
![y_1 = \frac{24}{4} = 6](https://tex.z-dn.net/?f=y_1%20%3D%20%5Cfrac%7B24%7D%7B4%7D%20%3D%206)
![y_2 = 24 - 18 = 6](https://tex.z-dn.net/?f=y_2%20%3D%2024%20-%2018%20%3D%206)
In both cases, ordered pair (24,6), thus <u>option A is the answer.</u>
A similar problem is given at brainly.com/question/22103476
Cos² 2x = (1+cos 4x )/2
cos² 6x = (1+cos 12x)/2
subtract to get 1/2 (cos 4x - cos 12x )
= 1/2 (2 sin 4x sin 8x ) as cos A - cos B = 2 [ sin (A+B)/2 sin (A-B)/2 ]
so the answer